Everything matters more in October. Just ask Mike Trout, who longs to prove himself this time of year. Or Clayton Kershaw, whose postseason accomplishments are so often under the microscope that how could they ever be good enough? Heck, ask George Springer, last season’s postseason star, whose life and career hasn’t been too bad since winning the World Series MVP.

As we enter the time of the baseball season where the game matters more, we also expect that the stars who play the games will have performances that matter more. Inevitably, that means players have something to prove each October.

It could be the guy trying to make up for past postseason struggles, the veteran finally getting a chance to make his mark in October or the young star whose talent will now get noticed more.

Here are 12 players — well, one is a group of players — who we’ll be watching a little more closely this month:

Giancarlo Stanton, New York Yankees

Stanton will make his postseason debut in the AL wild-card game and he’ll do so with an oftentimes unforgiving fanbase watching. If you thought the treatment Stanton received for a little slump in April was harsh, well, imagine it in October. Of course, if Stanton comes through, he will be the toast of the town. Now is the time to truly earn those Yankees pinstripes. (Mark Townsend)

Manny Machado, Los Angeles Dodgers

There is a lot on the line for the Dodgers and Manny Machado. Machado was the biggest trade acquisition of the deadline and is entering free agency this winter. The Dodgers have now won six straight NL West titles, but no World Series championships since 1988. Machado will need to deliver in October for the Dodgers’ sake and his own. (Johnny Flores)

Chris Sale, Boston Red Sox

Chris Sale has only pitched in the postseason twice and it was last year. He has an ERA north of eight and was shellacked for nine runs across two games against the Astros. His ability to be effective and remain healthy will be paramount to Boston securing a World Series title. (Johnny Flores)

David Price, Boston Red Sox

Price is something of a fixture on these types of lists. His postseason woes have followed him for years, and probably been less amplified because Clayton Kershaw’s are even more famous. Price, yet again, has a lot of prove. We know about the massive contract on which he’d underdelivered in Boston until this season. Price not only put together a respectable 2018 (16-7 with a 3.58 ERA), he was really good in the second half (6-1, 2.25). The Red Sox have enough pitching question marks — Sale’s health, their bullpen — that a really solid October by Price could endear him to Boston fans for years to come and perhaps change his postseason rep. (Mike Oz)

Carlos Correa, Houston Astros

If Correa’s 2017 season was a dream, 2018 was a nightmare. He missed seven weeks with a back issue, and after returning in mid-August, he hit .180/.261/.256 in his last 37 games of the regular season. The Astros didn’t need him or his bat to make it to the playoffs, but they might need him to be his old self once the playoffs actually begin. Correa has years to prove 2018 was a fluke, but only a handful of games left to be truly useful in 2018. If he can be productive in the playoffs, he could get a head start on proving he’s better than what he showed in 2018, and help the Astros win the World Series in the process. (Liz Roscher)

Matt Chapman, Oakland Athletics

It’s possible Matt Chapman is the most underrated player in baseball. When the A’s do get attention, most of the focus is on Khris Davis and his power. Chapman can do a lot more than hit home runs. In his sophomore season, Chapman improved virtually all of his offensive numbers. Defensively, he might be the best fielding third baseman in the American League. If the A’s can make some noise, it could be a coming out party for Chapman. Can he be the superstar player the A’s can build around for years to come? This is a chance for the baseball world to find out. (Chris Cwik)

Ronald Acuña Jr., Atlanta Braves

So many names here are clearly talented ballplayers trying to overcome a history of playoff disappointment, but in the case of Ronald Acuña, we’re just here to wonder how much hype the Atlanta Braves phenom can possibly build. The No. 1 prospect in baseball ranked by Baseball America entering this season, the 20-year-old Acuña more than lived up to expectations with a team-leading .917 OPS, 26 homers and 16 steals. Add in a strong postseason performance, and there will be even less doubt that the outfielder is on his way to becoming a bona fide superstar. (Jack Baer)

Clayton Kershaw, Los Angeles Dodgers

Quite possibly the patron saint of MLB players with something to prove in the postseason, it, unfortunately, looks like we’re entering a new stage of Clayton Kershaw’s career. He hasn’t won a Cy Young Award since 2014 and he hasn’t cleared 200 innings since 2015 due to injuries. Kershaw’s days as the undisputed top ace in baseball could be over, but that would likely matter little to the southpaw if he can put together the kind of playoff performance that has eluded him in his career. Add in the fact that Kershaw can enter free agency this offseason, and you have someone with as much to play for as you’ll find this postseason. (Jack Baer)

Trevor Bauer, Cleveland Indians

Corey Kluber may be Cleveland’s ace, but Trevor Bauer was their best pitcher in 2018. Bauer had a lower ERA, lower home-run rate and higher strikeout rate than Kluber this season. Problem is, Bauer may not be at 100 percent for the playoffs. A broken fibula sidelined Bauer from mid-August to late September. While he returned, we still haven’t seen him go deep into a game. If he pitches like he did in July, Cleveland is a huge threat. If he pitches like a guy coming off an injury, we could get a repeat of his post-drone injury starts in 2016. (Chris Cwik)

Christian Yelich, Milwaukee Brewers

It seems insane to have Christian Yelich on a list of players with anything to prove. After escaping/being traded from Miami to Milwaukee, he leads the National League in a bunch of categories and is the likely NL MVP. He’s headed to the playoffs for the very first time with a team full of exciting, excited players. He has nothing left to prove to anyone. But has he truly left Marlins Park behind? A great postseason showing, and helping the Brewers to success in their first playoff appearance since 2011, would prove that Yelich has shaken off Miami for good. (Liz Roscher)

The Rockies starting rotation

We’re sure a lot of people are wondering if the Rockies young rotation is for real. There is no better litmus test than the postseason. Kyle Freeland, German Marquez and Tyler Anderson could all make their October debuts, while Jon Gray has something to prove following last year’s wild-card game and his 2018 struggles. Let’s see if these Rockies have staying power. (Mark Townsend)

Roberto Osuna, Astros

No move in MLB this season produced more controversy than the Houston Astros trading for Toronto Blue Jays closer Roberto Osuna, who at the time was coming off a domestic violence suspension from MLB. The Osuna trade pitted a team’s desire to win against its role as a citizen. Osuna has been good on the field since joining the Astros (a 1.99 ERA and 12 saves), and just recently the criminal side of the allegations against him were settled. Now, it’s time to focus on baseball and he’ll likely meet boos and questions everywhere he goes. Unlike the rest of these players who have to prove themselves on the field, Osuna has to prove himself as a human being when the most attention is on him. (Mike Oz)

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Mike Oz is a writer at Yahoo Sports. Contact him at mikeozstew@yahoo.com or follow him on Twitter! Follow @MikeOz

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