First Pitch: These X-factors could make or break every MLB contender

Everyone expects the star players to show up in October. Aaron Judge's inability to do so is the main reason why the New York Yankees haven't won a World Series title. The Los Angeles Dodgers getting a superhuman performance from Freddie Freeman on one leg is a huge reason why they were able to win last season's World Series.

But while stars have to shine bright in October, it takes more than one or two players to win in MLB. I mean, why else would a team led by Shohei Ohtani and Mike Trout miss the playoffs every year for over a half decade?

Ultimately, it comes down to X-factors in October more often than not. Sure, Freeman was the star of the World Series, but the Dodgers might not get there without Tommy Edman. Would the Yankees have won the last year's pennant without Giancarlo Stanton, a player many wrote off prior to his October heroics?

Each team has at least one X-factor it needs to show up in order to win in October. Here's a list of players who you might not expect much from, but who must show up for their respective teams to win it all.

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Jack Flaherty, Detroit Tigers

The Detroit Tigers are a team built around Tarik Skubal, the best pitcher on the planet. Sure, he only pitches once every five days, but he's on pace to win his second straight Cy Young Award and has led the Tigers to a 19-7 record when he's taken the ball. For context, the Tigers are 59-49 when he isn't pitching; sure, they're still a good team, but Skubal is the guy who makes them a contender.

With that being said, as great as Skubal is, he cannot do it himself, especially as a starting pitcher. Others are going to have to step up. We all expect the likes of Riley Greene, Kerry Carpenter and Colt Keith to do so offensively, and Kyle Finnegan has been nothing but dominant in relief while wearing a Tigers uniform. But the question remains: Who is this team's No. 2 starter?

Jack Flaherty was supposed to be that guy after a resurgent 2024 campaign, but this season has been a rough one for the right-hander. He's posted a 4.87 ERA in 26 starts and 136.2 innings of work and has taken a league-leading 13 losses. No, the win-loss stat doesn't mean much in the grand scheme of things, but his propensity to implode any time he takes the ball is the main reason behind that record.

Flaherty has allowed seven or more runs three times, five or more runs six times and four or more runs eight times in his 26 appearances. He's also allowed one run or fewer eight times. It feels like he's as boom or bust as it gets in the game. If he's on, the Tigers become scary. If he's off, they're very beatable. Flaherty is their most talented non-Skubal pitcher, and will surely get the ball in October even despite his high ERA. Which version of Flaherty will we see? That could be the difference.

Daulton Varsho, Toronto Blue Jays

The Toronto Blue Jays have been one of, if not the best team in MLB for a couple of months now, but there's one glaring question: Can they hit enough home runs in October? The Jays rank eighth in the American League in homers, second-to-last among teams currently in AL postseason positioning.

George Springer has had a resurgent season and is an October legend, and Vladimir Guerrero Jr. can always run into one, but who else is there to hit the ball out of the yard? Stringing hits together is hard enough in the regular season, and becomes much tougher against elite pitching in October. The Jays hope that Anthony Santander can return from injury and provide a power boost, but can that really be expected considering how badly he played pre-injury and how long he's been out? Daulton Varsho, however, can be the power source they desperately need.

Varsho has been limited to just 45 games this season due to injury, but he's hit 15 home runs and 175 plate appearances, going yard once every 11.6 times he steps up to the plate. Here's how that number matches up against the game's elite sluggers.

Varsho has been as prolific of a home run hitter as anybody this season. I'm not saying he's on the level of these established superstars, but he's been going yard at an absurd rate. Having him hit behind the likes of Guerrero and Bo Bichette gives the Jays golden opportunities to put up crooked numbers in any given inning, something critical to winning in October. Hopefully, he can keep up this pace in October. If so, the Jays become even more dangerous than they already are.

Christian Walker, Houston Astros

The Houston Astros probably have the best one-two punch in an MLB rotation right now with Hunter Brown and Framber Valdez leading the way, and their dynamic duo of Josh Hader (when healthy) and Bryan Abreu is as good as it gets out of the bullpen. What's held this team back from running away with the AL West division has been their offense.

Yordan Alvarez's injury has obviously played a major role there, but the disappointing season Christian Walker has had has contributed as well. Walker was brought in to be a middle-of-the-order bat for Houston, but his .705 OPS and 96 wRC+ suggest he's been anything but.

Well, the tides have turned a bit in the second half, as Walker has slashed .252/.340/.481 with seven home runs and 25 RBI since the All-Star break. He's been much better, and what's really notable is that when he's able to produce, the Astros are dominant — and when he isn't, they have trouble winning games.

The Astros are 72-60 overall and hold a 1.5-game lead over the Seattle Mariners in the AL West. When Walker hits a home run or even drives in a run, they're practically unbeatable. When Walker doesn't drive in a run, they're a sub-.500 team. Obviously, any team would be better with production from anybody, but these numbers feel stark. The Astros are a team that wouldn't make the playoffs without Walker doing anything and they're a team capable of beating anybody when he does.

This isn't an accident. The Astros have come to expect guys like Alvarez, Jose Altuve and Jeremy Pena to step up, but again, contributions from others are needed. Walker producing lengthens their lineup and gives them a power threat teams cannot ignore. Hopefully he can do that in October.

Boston Red Sox, Brayan Bello

When the trade deadline wrapped up, Boston Red Sox fans weren't thrilled, mainly because Craig Breslow failed to acquire a starting pitcher they could rely on to slot in behind Garrett Crochet in October. They were in talks with the Minnesota Twins for Joe Ryan, a perfect fit in their rotation, but no matter how badly FOX Sports might've wanted a deal to go through, no deal was made.

As disappointing as it was to not see Breslow go all-in, the Red Sox might have a No. 2 starter in-house in Brayan Bello. Bello was nothing but inconsistent in his first three MLB seasons and got off to a rocky start to begin the 2025 campaign, but he's posted a 2.75 ERA in his last 15 starts since June 1 while averaging an outstanding 6.3 innings per start. He's gone at least six frames in all but three of these appearances and has allowed three earned runs or fewer in all but one of them.

Sure, it'd be nice if he struck out a couple more guys per outing, and the walks are a tad high, but overall, he's done a great job limiting contact — and frankly, the results speak for themselves. And what really sticks out about Bello is the fact that he has a 2.69 ERA in 11 starts against teams at or above .500, nearly a run better than the 3.44 mark he has against losing teams. Bello has been able to consistently step his game up against the best competition, giving Red Sox fans hope he can deliver when it matters most.

If Bello can be the Crochet's Robin, this Red Sox team becomes scary. If the Red Sox don't have a No. 2 starter, it's hard to envision them winning multiple seven-game series.

New York Yankees, Tim Hill

When thinking of the New York Yankees' bullpen, the mind immediately goes to guys like Devin Williams and Luke Weaver, or even the guys they acquired at the trade deadline, David Bednar and Camilo Doval. All of those names will obviously have to step up in October, but you already knew that. One guy who is constantly overlooked who also has to dominate in a very defined October role is Tim Hill.

As things stand right now, Hill is the only left-handed reliever in the Yankees' bullpen, and there's a good chance that'll remain the case in October. With that in mind, Aaron Boone is going to lean heavily on the veteran southpaw to get the elite lefty hitters out.

From Yordan Alvarez to Roman Anthony to Josh Naylor to Daulton Varsho to Riley Greene, there's no shortage of left-handed superstars in the American League. Being able to use Hill to get a big out or two against an elite left-handed hitter could really come in handy. Based on the fact that Hill has held left-handed hitters to a .157/.209/.167 slash line this season, Yankees fans should be confident he'll get the job done whenever he's called upon.

Ultimately, it's on Boone to deploy him in the right situations, something he notoriously failed to do in Game 1 of last year's World Series.

Seattle Mariners, Gabe Speier

If I'm being honest, it was a bit difficult to pick an X-factor for the Seattle Mariners because I'm a big believer in their roster as a whole and think they've got stars all over the place. Their rotation, particularly at home, is dominant. The first five or six hitters of their lineup are really, really good. The back-end of their bullpen, Matt Brash and Andres Munoz, is as good as it gets. With that being said, I do have questions regarding the rest of their relief corps, and that starts with Gabe Speier.

Speier has had a breakout year, posting a 2.17 ERA in 60 appearances while striking out 65 batters compared to just 10 walks. The southpaw has been particularly dominant against left-handed hitters, holding them to a .153/.191/.271 slash line in 89 plate appearances this season. He's settled into a set-up role in front of Brash and Munoz, but can he do this in October?

The 30-year-old has never had much success at the MLB level prior to this season, and he hasn't thrown a single postseason pitch in his career. If Speier can keep this up as the seventh-inning man in October following their elite rotation and setting up for Brash and Munoz, watch out. If he can't, perhaps the Mariners aren't as scary as I think they are.

Milwaukee Brewers, Andrew Vaughn

Similarly to the Toronto Blue Jays, the Milwaukee Brewers are an elite team reliant on great defense, making contact and wreaking havoc when the ball's in play. Those are great traits to have, but the absence of power is notable: Milwaukee is just seventh in the National League in home runs, and only one team currently in a playoff spot ranks below them. Given how hard it is to string hits together in October, they're going to need guys to hit some home runs to win postseason games.

The Brewers expect guys like Christian Yelich, William Contreras and Jackson Chourio to provide the bulk of the pop, but in his short time in Milwaukee, Andrew Vaughn has shown he can be that guy too. In just 40 games and 167 plate appearances, Vaughn has hit nine home runs and driven in 38 runs. Milwaukee has gone 8-1 when he's hit a home run and they've gone 17-2 in games where he's driven in at least one run. Sure, they've been winning practically every day lately regardless, but Vaughn has clearly made them better.

As of now, I'd say he deserves the first-base reps over Rhys Hoskins whenever the latter comes back from the IL, and if he can hit for power in October, good luck beating the Brewers.

Philadelphia Phillies, J.T. Realmuto

It feels like every year, the Philadelphia Phillies' season ends because their offense just doesn't show up. Last season, the Phillies scored just 12 runs in the NLDS against the New York Mets, and seven of those runs came in one game. Unsurprisingly, they lost the other three games in which they scored a total of five runs, leading to their early exit. Unfortunately, they could be headed toward the same fate this season because of how their lineup has performed.

Kyle Schwarber is an NL MVP candidate, Bryce Harper is still a superstar and Trea Turner has played as well as he ever has with the Phillies, but who else is there in their lineup? Their next-best hitter has been J.T. Realmuto, who has a 104 wRC+, just four points above the league-average. Because of that, he's been hitting clean-up consistently for around a month now.

This is certainly deserved, as Realmuto has an .860 OPS since the start of July, but can this carry over into October? It's worth noting that Realmuto went 0-for-11 in last year's NLDS. Having him produce offensively behind the big three could be the difference for Philadelphia.

Los Angeles Dodgers, Max Muncy

All eyes with the Los Angeles Dodgers are on the likes of Shohei Ohtani, Mookie Betts, Freddie Freeman, Will Smith and Teoscar Hernandez, and for good reason. But can we talk for a minute about how good Max Muncy has been? He's slashing .258/.389/.491 with 17 home runs and 64 RBI on the year, and to take things one step forward, he's been even better since addressing some vision issues back on April 30.

Muncy has slashed .295/.430/.611 since that date with 17 home runs and 60 RBI. He's gone from a clear weak link to a player performing at a superstar level for a lengthy period of time. In fact, here's where Muncy ranks among all NL players with at least 240 plate appearances since that date.

Muncy is currently on the IL, which is why he's only 12th in the league in fWAR, but on a per-game production basis, an argument can be made that Muncy has been the best player in the league. Yes, there are questions revolving around this Dodgers' pitching staff, but if Muncy is performing like this in October in a lineup that already has the most star power in the sport, Los Angeles might be a lock to repeat as World Series champions.

Chicago Cubs, Cade Horton

We all know that if the Chicago Cubs are going to win the World Series, their lineup is going to have to be much better than it has been since the All-Star break. For that to happen, stars like Kyle Tucker, Pete Crow-Armstrong and Seiya Suzuki need to play like stars. but another thing that has to happen is that the rotation must step up.

Justin Steele is out for the year, putting pressure on everyone else. Someone who has stepped up in that void and done so somewhat under the radar has been rookie Cade Horton, who has gone from a question mark to arguably the best starting pitcher the Cubs have to offer.

Horton's overall numbers are good (2.88 ERA in 18 appearances, 17 starts), but what he's done lately has been absurd. The right-hander has posted a 1.11 ERA in his last nine starts since the beginning of July, and four of the six earned runs he's given up came in one outing. While Horton has certainly had his way with some lackluster competition, he's thrown the ball really well against some quality offenses like the Boston Red Sox and Toronto Blue Jays, and he's allowed only two home runs during this dominant stretch.

Can it continue into October, especially when he's already blown past his previous career high in innings pitched? I have no idea, but the Cubs sort of need it to. Steele is out, and I have questions regarding just how good Shota Imanaga and Matthew Boyd ultimately are. Having Horton step up would go a long way.

San Diego Padres, Dylan Cease

The San Diego Padres have by far the best bullpen in the Majors, but does it really matter if they don't have a lead to protect? This Padres starting rotation can be good, but I have questions. Can Michael King stay healthy? Will Nick Pivetta's breakout carry into October? And another one: What will the Padres get from Dylan Cease?

We know how good he is at his best. Cease was the AL Cy Young runner-up in 2022 and finished fourth in the Cy Young balloting last season with the Padres. Unfortunately, while he's continued to be among the most durable arms in the game, Cease's production has taken a nosedive this season, as he's posted a 4.82 ERA in 27 starts and 142 innings of work.

Some bad luck has certainly been involved, as Cease's 3.73 FIP is over a full run lower than his ERA and his strikeout rate is as high as it's been since 2022. But his home run rate is as high as it's been since 2020 and he leads the league in walks.

We've seen Cease at his best this season. He has quality starts against elite offenses like the New York Yankees, Toronto Blue Jays and Los Angeles Dodgers. We've also seen plenty of Cease clunkers. If he can give the Padres five or six strong innings as their second or third starter, San Diego will be really tough to beat given the state of their bullpen. If he can't, how many pitchers in this rotation can the Padres rely on? Again, they don't need much from their rotation, but they do need something to put their bullpen in position to shut it down.

New York Mets, Mark Vientos

We saw how good Mark Vientos can be last year. He broke out in a huge way in the regular season, hitting 27 home runs in just 111 games and posting a 135 OPS+. He was even better in the postseason, hitting as well as anyone in the New York Mets lineup. He entered 2025 with lofty expectations, but his production for the most part has been non-existent until recently.

Vientos' numbers are far from stellar, as he's slashing .243/.291/.419 with 12 home runs and 46 RBI in 92 games. His 101 OPS+ is just a tick above average. Lately, though, he's gone on a nine-game hitting streak, hitting five home runs and driving in 14 runs in those games with a 1.377 OPS. He's lifted his season OPS by nearly 80 points in this span.

Small sample size, sure, but having Vientos perform like this drastically changes things for the Mets. Their offense has been incredibly reliant on star players like Francisco Lindor, Juan Soto and Pete Alonso to carry the load. While the expectation should be for those guys to perform up to their billing, they can't do everything.

The Mets' offense has suddenly woken up lately, and it comes as no surprise that their turnaround has coincided with Vientos (among others) swinging the bat better. When he's on, he can hit home runs in bunches, and can help the Mets slug their way to the World Series.