Ending the regular season on a mediocre note doesn't totally ruin your chances come playoff time. But in MLB postseason history since division play began in 1969, the teams that win the World Series tend to be the ones who play about .600 ball in September and October.

And only four times out of 52 did the eventual World Series champ lose more than it won in the last portion of the regular season. It happened most recently with the Kansas City Royals in 2015. This year, the Tampa Bay Rays and Philadelphia Phillies are the teams having that additional bit of history against them as the playoffs begin.

With that context, we look at every team in the MLB postseason field to see what needs to happen for them to win it all. First up, the reigning champions.

Atlanta Braves (101-61)

They won 88 games a year ago during the regular season, but everyone remembers the troubled start before the huge second-half surge that included a World Series victory. It played out similarly this season, with the Braves going 23-27 in the first two months before putting it all together. No team had a better record after June 1 (the Dodgers were a half-game worse), and you could make a strong argument that Atlanta has yet to put it all together.

Matt Olson hasn't been as good as Freddie Freeman, as he struggled in the second half. Ozzie Albies has been out with an injury for more than half of the season. Ronald Acuña Jr. hasn't recovered fully from his ACL injury and is nowhere nearly as effective on either side of the ball as he was before August 2021. Left field and designated hitter have been trouble spots, with no one among Eddie Rosario, Adam Duvall, Robbie Grossman and Marcell Ozuna providing even league-average results.

How have the Braves gotten better? Austin Riley kicked it into an even higher gear after his breakthrough 2021 season. Dansby Swanson turned it up come playoff time in 2021 and hasn't slowed down. And the rookies. Outfielder Michael Harris II and right-hander Spencer Strider have been the two best rookies in the National League, maybe in all of MLB.

Max Fried has continued to be one of the best pitchers in the league, and Charlie Morton, at age 38, is most of what he was a year ago. Kyle Wright broke through to be a Cy Young candidate, but Ian Anderson seemed to have a workload hangover all season. The bullpen is still one of the best in the league, with Tyler Matzek and A.J. Minter as key holdovers from 2021 and Kenley Jansen, Collin McHugh and Raisel Iglesias as important newcomers.

Atlanta wasn't going to win the World Series again with the same team as 2021, and general manager Alex Anthopoulos made a lot of positive changes. It's almost easier to find the reasons why the Braves won't win it all again. The only seriously troubling statistic about them — like, at all — is that they went 2-4 against the Dodgers.

Possibly mildly troubling is their performance against other teams they might face in the postseason. They went 11-8 against Philadelphia (with the scoring 88-85). It's obviously not bad, but it's definitely not dominating. They went 4-3 against St. Louis (outscoring the Cardinals 37-23), and that's better, for sure. Atlanta certainly finished strong against the Mets, but only won the season series 10-9. And it dropped four of seven against the Padres — although all of it happened in the April-May down period.

Cleveland Guardians (92-70)

Cleveland probably had the least collective public support in the preseason to make the playoffs. Most prognosticators picked the Chicago White Sox or Minnesota Twins to win the American League Central, and while it took most of the season for the Guardians to separate themselves from the so-called favorites, they did so in an extreme way down the stretch.

Cleveland went 10-2 against Minnesota and Chicago from Sept. 9-22, gaining 5 1/2 games on its closest pursuers during that span. Such an effective focus has to bother any potential opponent in the playoffs.

The offense is middle-of-the-road overall, but it's third in runs scored in the final month as the Guardians pulled away in the division. What they don't do much: hit home runs. They had 127. Only the Detroit Tigers (110) hit fewer in 2022.

It is possible for a team without much home-run clout to win the World Series — the Kansas City Royals finished 24th in home runs in 2015 and won the title anyway (but they also hit a total of 17 homers in three playoff rounds), and the 2012 San Francisco Giants, who finished dead last in homers in the regular season. hit 14 home runs in 16 postseason games. Hitting homers is not what the Guardians do best, but they likely will need the long ball to win in the postseason.

Rookie leadoff man Steven Kwan has been close to scoring a run per game during the late-season push, while Andres Giménez and Oscar González continue to hit at high levels. What Cleveland doesn’t have is the best possible contribution from José Ramírez, who has been about 10% above average over the past three months. That the Guardians have gone from a .500 team to reaching 90 victories without a huge surge from Ramírez also shows how dangerous they could be to the rest of the league if he gets hot.

Cleveland keeps the scores low with great pitching (only the Los Angeles Dodgers and Houston Astros have lower team ERAs in the second half), notably from ace Shane Bieber and Triston McKenzie. The Guardians will need to keep putting up zeroes. Cal Quantrill and Aaron Civale won't strike fear into hitters in the same way, but both are effective and have been stronger down the stretch. The bullpen is deep and elite at the end with closer Emmanuel Clase, and setup arm James Karinchak has been revitalized after having grip issues.

They also have manager Terry Francona, who gives them the best leadership possible. The franchise hasn't won a World Series since 1948, and that remains the focus.

Houston Astros (106-56)

Houston probably has the best team in the AL. Since July 1, only the Dodgers and Braves have a better record. Overall, the Astros have the second-best ERA (2.90) and the best ERA among relievers (2.80). They also have the eighth-best offense in the majors (737 runs) as well as the fifth-best defense, per Fielding Bible. Their hitters hardly strike out (only Cleveland was better), and their pitchers rank fourth in getting strikeouts (1,524). They have few weaknesses.

Justin Verlander finished the season healthy, and his 1.75 ERA makes him the AL Cy Young favorite. Right-hander Cristian Javier has a 0.32 ERA in his past five starts. Left-hander Framber Valdez, while mediocre in the final month of the season, is one of the top 10 to 15 starters. He also aced one of the more pivotal games of Houston's previous postseason, AL Championship Series Game 5 against the Red Sox, in 2021.

A big playoff key likely will be Lance McCullers, who returned from a scary and time-consuming forearm injury he sustained in the postseason a year ago to post a 2.27 ERA in eight starts down the stretch. His presence means Luis García is the fifth starter and swingman, which is just ridiculous depth, and puts the bullpen in position to be perhaps the most effective in the playoffs. Ryan Pressly, Ryne Stanek and Rafael Montero get it done.

Houston has three or four big weapons on offense it could ride to a title. José Altuve went under the radar, so to speak, and had the top hitting season of his career. He had his highest walk rate, his second-best isolated power and best wRC+. Only three hitters in the majors have been better. He's also a .286/.361/.547 hitter with 23 home runs in 79 career postseason games.

Yordan Álvarez is better. Only Aaron Judge had a better year at the plate. Álvarez is a career .277/.388/.455 hitter in the postseason, but he is capable of putting up something like .566/.612/.991 in a given series. For the Astros to find that extra gear, Alex Bregman likely will have to hit like he did in August (.362/.452/.681 with seven homers, 17 walks and 10 strikeouts in 115 plate appearances). He had his best season since 2019 but is still not back to MVP candidate form.

Lefty slugger Kyle Tucker can't be tamed by left-handed pitching, but his overall production this season was merely very good. He was better in 2021 and probably will be better going forward. A potential fifth wheel in the lineup is rookie Jeremy Peña, who put up league-average stats overall but had one of his best months (.278/.303/.487 with six homers) to finish the regular season.

This is your periodic reminder that manager Dusty Baker is still looking for his first championship. He likely will have no better opportunity.

Los Angeles Dodgers (111-51)

The Dodgers scored the most runs (847), and they allowed the fewest (513). Only four teams hit more home runs than their 212. Only five teams allowed fewer homers than their 152. Only one team drew more walks than their 607. They allowed the fewest baserunners. They have the second-best defense, per Fielding Bible. They have two NL MVP candidates (Mookie Betts and Freddie Freeman) hitting among the first three batters in their order. They have the NL's ERA champion in Julio Urias (2.16), and they have another pitcher with a lower ERA in their rotation (Tony Gonsolin, 2.14) who just didn't have enough innings to qualify.

L.A. has two more All-Stars in its rotation, and one of them (Clayton Kershaw) is a future Hall of Famer. (Tyler Anderson is the other.) Kershaw is having his best personal season in six years, and his peripheral numbers, notably his DRA-, are better than all of the other Dodgers starters — except for left-hander Andrew Heaney, who probably won't even be used as a starter in the postseason. That's some depth.

Nobody, except for perhaps Houston, has better bullpen depth than the Dodgers, but, like the Yankees, injuries and other circumstances might play havoc with the roles. Expensive closer Craig Kimbrel (like the Yanks' Aroldis Chapman) probably won't finish games. Brusdar Graterol has made only nine appearances in the second half. Dustin May and Blake Treinen don't seem to be ready to pitch out of the gate. L.A.’s top performers in relief are right-hander Evan Phillips and left-hander Alex Vesia, and while both have some postseason experience, their team would be depending on more, with higher-leverage situations, this time around.

The Dodgers need more than Betts and Freeman to be productive, with the next most important sluggers being Trea Turner, Max Muncy, Will Smith and Justin Turner. They don't need all of them to hit all of the time, but it must be nice to have so many above-average options. It's going to take an opponent's best effort to stop a three-quarters effort by L.A.

New York Mets (101-61)

It would be easy to call the Mets cooked after their disappointing turn against Atlanta in the regular season. But they're still one of four teams to win at least 100 games.

They have the scariest 1-2 punch in any pitching rotation, with Jacob deGrom and Max Scherzer. Edwin Diaz is the best relief pitcher. They have the fifth-best offense in the majors (772 runs), although that's including Starling Marte who might not be available at the start of the playoffs on Friday. They're probably going to need him and have a few other things break their way — most notably having deGrom and Scherzer be better than they were at Truist Field against the Braves.

If their aces pitch their best — and a plurality of Pete Alonso, Francisco Lindor, Jeff McNeil, Eduardo Escobar, Brandon Nimmo, Mark Canha and Daniel Vogelbach can keep the (7) line moving — the Mets can go as far in the playoffs as it looked like they might before getting caught and surpassed by Atlanta in the NL East standings.

New York Yankees (99-63)

The really big question with them is: Will Aaron Judge ever go deep again? Kidding of course, but it's no doubt going to feel like a relief for Judge to be done with the Roger Maris record chase and to be getting on with the old-fashioned pressure of the playoffs.

Judge has 11 home runs in 35 career postseason games, so he's not one to let the postseason environment bother him. To be clear, he had one of the best regular seasons of any hitter in history, so it's reasonable to expect a Yankees championship to go concurrently with him going yard a lot in October.

Overall, the Yankees have MLB’s No. 2 offense in runs scored (807), with Anthony Rizzo being their second-best hitter. It's not his first postseason rodeo, and when the Cubs won the World Series in 2016, Rizzo hit .277/.373/.492 with three home runs in 17 games. Something like that from Rizzo probably has to happen for the Yankees to win their 28th championship.

The rest of the Yankees lineup was much closer to ordinary this season, but among the everyday players, another likely key will be Giancarlo Stanton, a career .297/.373/.734 hitter with nine home runs in 18 postseason games with the Yankees. It also remains to be seen if injured sluggers Andrew Benintendi or Matt Carpenter (who was hitting home runs like crazy before going down) will be healthy enough to play. If not, there will be more opportunities for Venezuelan rookies Oswald Peraza and Oswaldo Cabrera, who both have performed well down the stretch.

The Yankees have much better starting pitching depth than in recent seasons — only the Dodgers and Astros have been better by average — but it's still mysterious exactly what they'll get from the group.

Gerrit Cole's velocity has been down just enough to make him more vulnerable to home runs. Left-hander Nestor Cortes didn't get a chance to pitch in the playoffs last year, but he'll need to play a huge role this time if the Yankees want to get back to the World Series. Domingo Germán, Jameson Taillon and Luis Severino got the job done in the regular season, but Germán and Taillon have zero postseason appearances. Also, Severino's experience in the playoffs has been hit or miss. New York will need multiple successful outings from this group to be king of the hill this year.

The Yankees have had a plus bullpen, but late-season injury questions cloud its future. With Aroldis Chapman pitching ineffectively, Clay Holmes being recently injured and Wandy Peralta trying to come back from an injury, is Scott Effross ready to be a go-to guy in the ninth inning? New York also has effective setup options like Jonathan Loáisiga, Clark Schmidt and Lou Trivino, but October is not a good time to be hemorrhaging depth. It might take something like Chapman finding his command with the snap of the fingers to put the Yankees over the top.

A factor in the Yankees' favor is defense: They have, by far, the best in the league, per Fielding Bible. They've saved 126 runs; next best is the Dodgers at 86. League average is about 17; the worst was the Giants at negative-56.

Philadelphia Phillies (87-75)

They can control any short series in which they play because they have right-handers Zack Wheeler and Aaron Nola in the same rotation. Both could put up zeroes for seven to eight innings against any opponent in the field, which only a few teams in the postseason can be as certain about. Getting to the World Series also would require left-hander Ranger Suárez, who has a 2.33 ERA in his past 13 starts, to continue that path.

The Phillies aren’t stocked with much pitching depth, but relievers Seranthony Dominguez, David Robertson and Jose Alvarado can lock down the back end if they're not overextended. And just like everyone said before the season, Philly will have to slug in order to win. That means Bryce Harper, Kyle Schwarber, Rhys Hoskins and J.T. Realmuto will have to do their thing. Also, it wouldn’t hurt if Nick Castellanos emerged from his season-long slump to at least be a solid complementary hitter, as Jean Segura and Alec Bohm are.

Philadelphia scored the seventh-most runs (747) in the majors, but it can do a lot better. If the offense starts to roll, the Phillies can go a long way in the playoffs.

St. Louis Cardinals (93-69)

Is this another Cardinals Devil Magic season like 2006, when they won 83 games in the regular season before rolling through the playoffs? They have several established stars having great seasons — MVP candidates like Nolan Arenado and Paul Goldschmidt. They have a strong influx of rookies who have played a big role — infielder Brendan Donovan, outfielder Lars Nootbaar and pitcher Andre Pallante, most notably. They have supporting players typical of what team president John Mozeliak provides — Miles Mikolas, Jordan Montgomery and Tommy Edman.

They also have some Devil Magic.

How else can Adam Wainwright's late-career rebound be explained? Or whatever got into Albert Pujols at age 42? Wainwright isn't quite performing like 2009 and neither is Pujols, but they might have enough left to take St. Louis all the way this time. And don't be surprised if Yadier Molina does something unlikely in the playoffs. He doesn't want his only championship this season to come on the basketball court.

The Cardinals do have a few obstacles to climb. It doesn't look like they'll have Tyler O'Neill ready for the playoffs. They'll need someone like Dylan Carlson to break out of his season-long funk and make up for O'Neill's loss and the hole left in center field by the Harrison Bader trade. They'll need Molina to find a higher gear, if he can. They'll need right-hander Jack Flaherty to put it all together (or at least back together) after injuries have disrupted his career.

If all of that happens, St. Louis can win its 12th championship in club history.

San Diego Padres (89-73)

Behind manager Bob Melvin, the Padres already have done what they couldn't do a year ago under different leadership: navigate several significant obstacles and make the playoffs. Asking them to do much more this time might be a tall order, especially considering they have to face an opponent that has triple-digit victories during the regular season. But they do have a puncher's chance largely because of six individuals.

Yu Darvish, Joe Musgrove and Blake Snell are three top-25 pitchers who can shut down any lineup at any time with no-hit or low-hit stuff. The only scarier rotation is probably the Mets, who happen to be San Diego's first-round opponent. New York won't face a bigger challenge from a group of starters in the playoffs.

The other X-factor is closer Josh Hader, whose performance fell off completely this season with the Milwaukee Brewers and his first month with the Padres. But since Aug. 31, Hader has allowed one earned run, five hits and two walks to go with 14 strikeouts in 11 1/3 innings. It seems like he's back to being one of the top relievers in the game.

On offense, it will be up to Manny Machado and Juan Soto. Machado is an NL MVP candidate who's having the best full season of his career (.296/.366/.530 with 32 homers). Soto was one of the five best hitters in the league since he came up in 2018 with the Washington Nationals, but he has slumped this year, particularly after being dealt to the Padres before the trade deadline.

If Soto can break out of his slump and return to his true form, well, the Padres become a problem for whomever they face in the playoffs.

Seattle Mariners (90-72)

Seattle broke a 21-year playoff drought thanks in large part to a team ERA (3.59, eighth in MLB) that is about as good as the Guardians (3.46, sixth) and the Mets (3.57, seventh). However, the Mariners won't have any home games in the wild-card round against Toronto to help them. Still, they have been a solid team away from T-Mobile Park, finishing with a road record (44-37) about as good as Atlanta's (46-35).

The M's basically have been a .500 team since Sept. 1, but we're starting over now. Left-hander Robbie Ray, Luis Castillo, Logan Gilbert and rookie George Kirby give Seattle four starting pitchers in the top 40 or so overall, with Castillo being the ace. Most teams envy this kind of strong footing.

The bullpen is solid without many widely known parts (Diego Castillo being an exception). Right-hander Andrés Muñoz has emerged as one of the top 10-15 relievers in the league, and Matt Brash, who has some ridiculous movement on his pitches, has become a key setup man for closer Paul Sewald.

One thing you can't discount with all of Seattle's pitching: Catcher Cal Raleigh is one of the best at grabbing extra strikes.

The offense is mediocre, so having rookie Julio Rodríguez near 100% is a must. He has spent much of the past month on the IL because of a sore back. He'll need to start hitting bombs — and so will Mitch Haniger — for the Mariners to have a long shelf life in the playoffs. This is also assuming that Eugenio Suárez and Ty France are producing and someone among Adam Frazier, Jesse Winker and Carlos Santana gets hot at the plate.

A possible wild card: One-time top prospect Jarred Kelenic, who for his career is about 30% below average as a hitter, recently had a week where he was crushing the ball. If he got close to being right in the playoffs, maybe in a Cody Bellinger way, it could flip things in Seattle's favor.

Tampa Bay Rays (86-76)

The Rays did pretty well to finish with a win total in the 80s — in the AL East, no less — after not having big chunks of their lineup healthy all season. The biggest key to a successful postseason, presuming their pitching can keep Cleveland (and the others) in check, is a return to form of Wander Franco. After a fast start, he sustained a quad injury and, later, a right wrist injury that required surgery on his hamate bone. He returned to the lineup on Sept. 9, and since Sept. 19, he's hitting more like pre-injury Franco.

He can't do it alone, which means perennial Rookie of the Year candidate (but not this season) Randy Arozarena will need to get clicking as well. He is a .354/.436/.760 hitter with 11 home runs in 29 postseason games. Yes, 11 homers!

Back to the pitching: Tampa Bay has the majors' seventh-lowest bullpen ERA (3.36) but also relies on its relievers for more innings than any other team. The bullpen is typically anonymous but just as effective. The starters have the third-best ERA (3.45) among all teams, with left-hander Shane McClanahan the presumptive ace. However, since a late-season injury, he hasn't been pitching like his All-Star self. He'll need to relight the fire.

McClanahan can't be counted on for a full workload, but the Rays will have Tyler Glasnow available for perhaps 75 pitches per outing after his return from Tommy John surgery. Drew Rasmussen and Jeffrey Springs have been two of the 20 best pitchers in the second half. Tampa Bay is looking for its third World Series appearance in franchise history and its first championship.

Toronto Blue Jays (92-70)

The Blue Jays have MLB's fourth-best offense (775 runs), but it hasn't been carried by Vladimir Guerrero like one might expect. The 2021 AL MVP runner-up is no better than the second-best hitter in his own lineup after George Springer, and he’s not measurably better than Bo Bichette, Teoscar Hernandez and Alejandro Kirk. In the second half, Guerrero has been about as good as Matt Chapman and Whit Merrifield.

What's different? Guerrero is not hitting the ball as hard as he did last season. He’s not hitting it in the air as much, he’s not walking as much and he's not as lucky. He's still good — Guerrero is about 25% better than the average hitter, though not much better than the average first baseman. Still, if he hits in the postseason like he did in April, June, July and August, his bat could be the jolt Toronto needs to move along.

The Jays are saying that the cut on Kevin Gausman's right middle finger is not a big concern for his next start, and they better not be blowing smoke. Gausman is a top-20 pitcher, and Alek Manoah is among the game’s elite starters. So they need to continue to perform at a high level in the postseason for Toronto to have a shot at late October.

Bigger questions lie with José Berríos, who has a big reputation and contract but also is having his worst season. Ross Stripling, who is having his best season in a solid career, could be asked to make playoff starts for the first time. Most of his appearances have been one-inning stints.

The bullpen is in the middle statistically, but it’s plenty capable of being one of the better ones in the postseason field. Jordan Romano is one of the best at the end of games, and Anthony Bass has been a big addition for innings 7-8-9.

The competition is fierce. The Braves, Dodgers, Astros and Yankees have the best teams to date. But it wouldn't be a huge stretch for the Mets, Cardinals or Phillies to win the Commissioner's Trophy, either. And it's not impossible for any of the teams still going.