October isn't about six months of numbers. It's about who is hot right now, for three days or seven, and that can be anyone from a slumping star, a middle reliever nobody outside the clubhouse has heard of and a player coming back from an injury – (Aaron Judge, anybody?).
Here's the X-factors for each playoff contender, the ones who could swing a series.
Tampa Bay Rays
Freddy Peralta was a disaster for six weeks after Tampa Bay acquired him from the New York Mets on Aug. 3, a 7.17 ERA over his first four starts with the Rays. Over his last five starts, he's allowed just three earned runs in 28 ⅔ innings (0.94 ERA). He's not entirely fixed, though. His outing on Sept. 13 was a near no-hitter against the Houston Astros, but it still took 86 pitches to get through
five innings because he walked three. If the newer version of Peralta shows up in October, the Rays have three dependable arms when including Drew Rasmussen and Nick Martinez. If the wild version shows up, the Rays might be walked out of the playoffs. If the version from August shows up, they are in trouble.
New York Yankees
The Yankees postseason hangs on the health of Aaron Judge. Just back after missing three months with a broken rib, Judge seemed to be getting back into form when he left the series finale against the Twins on Sept. 16 with a right calf strain. Manager Aaron Boone said the team is planning for Judge "not being a part" of the Yankees' wild-card series, but Judge insists he shouldn't be ruled out. New York has to hope it's just part of the ramp-up process, because without Judge in the lineup, the Yankees' October could be very short.
Boston Red Sox
Garrett Crochet hasn't pitched in a competitive game since April 25. The Red Sox ace has missed almost the entire season, first with the shoulder inflammation, then a lat strain. He's been ramping up over the past two weeks, throwing his sweeper off a mound for the first time on Sept. 11, and Boston is skipping a minor league rehab assignment entirely, aiming instead to get him into live batting practice in the season's final week. The plan, if he's ready, isn't to start him. It's to use him in short relief, like he did as a rookie with the White Sox. The Red Sox rallied to get into contention without him. If he can be effective with essentially no tune-up, that's a heck of a playoff weapon.
Chicago White Sox
Colson Montgomery is a 24-year-old having a 30-homer season, and striking out at a rate that's putting him in the company of the biggest whiff totals in White Sox history. He is also going through a brutal cold stretch at the wrong time: 4 for his last 49 with 29 strikeouts during that span. Getting hit by a pitch on Sept. 16 didn't help, though X-rays came back clean. After leading the AL Central from July 4 until Sept. 16, the White Sox are still on the Cleveland Guardians' tails. In a race that tight, Montgomery is either a middle-of-the order threat, or an easy out and nobody will know which until it happens.
Cleveland Guardians
Cleveland traded for Jo Adell on Aug. 3, needing a jolt of power while Jose Ramirez was still finding his timing back from hamate surgery. The Guardians got a hitter who's two different players depending on who's on the mound. Against left-handers this year, he has hit .321 with a .593 slugging percentage. Facing righties, he's hit .209 and been close to unplayable. Since the trade he's hit three home runs of at least 450 feet. How much of a factor he is for the Guardians depends on how many left-handers that they face and if manager Stephen Vogt is willing to sit him against the rest.
Houston Astros
Hunter Brown was a Cy Young contender for Houston in 2025 with a 2.43 ERA that put him in the conversation for the American League's best pitcher. A shoulder strain cost him from April to mid-June, and the version that came back still throws just as hard, but he's lost the command that made him elite. His walk rate has nearly doubled since returning, and his ERA over that stretch has run closer to 4.75 than the number that made him a star a year ago. Houston doesn't have much rotation depth to lean on if he's off. Cristian Javier has an ERA over 5, and the Astros have already turned to a bullpen game just to get through a rotation turn. Tied with Texas heading into the final week of the season, the Astros need Brown to find himself or it will be a short October.
Texas Rangers
If the Rangers get in, they'll go as far as Jacob deGrom lets them, and lately that has meant something different every turn through the rotation. DeGrom left an August start against the Angels after two innings with triceps fatigue. Three weeks later, he struck out 12 over six shutout innings against Seattle – then left that game early, too, this time with groin tightness. He came back on schedule and pitched through it against Boston with eight strikeouts over five innings. His ERA sits at 3.86 for the season. At 38, deGrom's stuff still looks like peak deGrom, but whether his body holds up long enough to carry the Rangers in October is the question.
Atlanta Braves
Ronald Acuna Jr. has played 100 games in a season only five times in his career, and this (barely) is one of those years. A hamstring strain cost him from June 9 to late July, and for a former MVP, his season line is pretty modest. He's hitting .259 with 20 home runs for the season, buoyed by an 18-game stretch where he hit .366 with 10 extra-base hits. Then he fouled a ball off his leg on Sept. 22, leaving the game with a left shin contusion. If Acuna can get back and pick up where he left off, that's the X-factor the Braves need.
Philadelphia Phillies
The Phillies rotation looked settled heading into September. Then Jesus Luzardo went on the injured list with left shoulder soreness, and Cristopher Sanchez, who has a 2.93 ERA for season, has put up a 4.48 ERA since July 1. That leaves Zack Wheeler as the only starter the Phillies don't have to worry about – even if he is coming off thoracic outlet surgery last year. Aaron Nola has a 3.03 ERA since the All-Star break, a real turnaround from a rocky start, and Andrew Painter has been nearly as good since midseason. How many of those arms steps up in October is going to be the difference between the Phillies celebrating or going home early.
Milwaukee Brewers
Trevor Megill opened the season so poorly that he briefly lost the closer's job. He posted a 14.40 ERA in April that included a blown save against Toronto. He turned it around with an 0.86 ERA over a 20-outing stretch that carried into July, but lately it looks like the heavy workload could be catching up (5.40 ERA in September). Milwaukee has the best record in baseball and a first-round bye, which will bring some much-needed rest for its closer. Which version of Megill shows up in October will determine how far the Brewers go.
Chicago Cubs
The Cubs' ninth inning is still up for grabs. Jacob Webb had it and put up a 24-appearance scoreless streak until he blew consecutive saves and has allowed 11 earned runs in his past nine innings. Daniel Palencia wants it back. He has a 100 mph fastball and 22 saves from a year ago, but he looked rusty coming off elbow inflammation in August, before stringing together enough clean outings that manager Craig Counsell called it the best stretch yet. Whoever is closing in October will hold the Cubs' fate in his hands.
Los Angeles Dodgers
Shohei Ohtani hadn't played in nearly two weeks, before returning Sept. 23. His two-way comeback ended for good in late August with biceps soreness that has since spread into his knee and neck. He says he feels good, but the Dodgers have already said he probably won't be at full strength in October. His season line, a .900 OPS with 30 home runs, still reads like an MVP, but since Aug. 8 he was hitting .198. Whether he can play at his elite level might be the single biggest X-factor heading into October.
San Diego Padres
The Padres rotation lost four projected starters to injury this year: Joe Musgrove, Lucas Giolito, Yu Darvish and Bryan Hoeing all done for the season. Michael King has emerged as the ace, and Walker Buehler has a 3.15 ERA over his past nine starts. Behind them it's a question mark. Nick Pivetta just came back from injury, and deadline pickups Robbie Ray and Casey Mize have settled in and a shaky start. Which of these arms the Padres can trust heading into October will make the difference.
This article originally appeared on USA TODAY: MLB playoff X-factors: One player who could swing October for every contender
