Ranking each playoff hopeful’s Game 1 starter after the Zack Wheeler injury

The Philadelphia Phillies were dealt what could be a season-defining blow with Zack Wheeler, the team's ace, suffering a season-ending injury. Sure, even without him Philadelphia's rotation is among the National League's elite, but few, if any, starters in the game are more reliable than Wheeler, particularly in October.

The right-hander has a 2.18 ERA in 12 postseason starts in his career. The Phillies lost his lone postseason start last season, but that was to no fault of his own, as Wheeler pitched seven shutout innings.

The Phillies can win the World Series, but doing so becomes much harder without Wheeler. With Wheeler out, Phillies fans are curious where his likely Game 1 replacement in a postseason series, Cristopher Sanchez, ranks among other aces. With that in mind, here's a ranking of every potential Game 1 starter for each team currently in postseason positioning.

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12) Shane Bieber, Toronto Blue Jays

I will start this off by saying when Shane Bieber is right, he's a lot higher on a list like this. Few starters in the American League are better than Shane Bieber at his best. Unfortunately, the right-hander has dealt with several injuries since winning the Cy Young award in 2020, and he's been limited to just three starts since the start of the 2024 campaign after undergoing Tommy John Surgery.

Knowing his upside is sky-high, the Toronto Blue Jays acquired Bieber in a trade deadline deal with the Cleveland Guardians. His Blue Jays debut couldn't have gone much better, as the right-hander allowed just one run on two hits in six innings, striking out nine and not issuing a single walk against the Miami Marlins. As encouraging as that was to see, it's hard to rank Bieber above other aces when he's made one start all year.

A strong finish to his season, though, will have Blue Jays fans extremely excited ahead of what could very well be an eventful postseason if Bieber is the Bieber of old.

11) Shota Imanaga, Chicago Cubs

The Chicago Cubs lost Justin Steele for the season, which hurts them exponentially for a potential Game 2 in the postseason, but they do still have Shota Imanaga healthy and, as his 3.03 ERA in 19 starts would indicate, having a solid season. While the results have certainly been there, a hot take of mine is I'm not sure it's sustainable for Imanaga.

His ERA is good, but his 4.32 FIP and his .213 BAbip suggests he's gotten extremely lucky. In fact, I'd argue he's been one of the luckiest pitchers in the game when looking at the E-F (ERA-FIP) metric on FanGraphs.

Imanaga's -1.30 E-F ranks 95th among 96 pitchers with at least 110 innings of work. The Cubs are a really strong defensive team which has helped Imanaga a ton, but when taking into account the fact that he ranks in the 28th percentile in average exit velocity, the 40th percentile in strikeout rate and the fourth percentile in ground ball rate (all per Baseball Savant), it's hard to expect him to outduel some of the National League's elite in October.

I do believe Imanaga is a good pitcher, but when he's allowing hard contact, not striking many guys out, and not keeping the ball on the ground, it's hard to expect ace-level production, especially against the National League's elite offenses in the postseason.

10) David Peterson, New York Mets

David Peterson is the least-known guy here, and might have the worst stuff of the bunch, but all the guy does is get the ball done. The New York Mets have struggled mightily to get any sort of consistent length out of their starters, but that's seemingly something Peterson gives them every fifth day.

The southpaw has a 3.18 ERA in 25 starts and 150 innings of work this season, and he has a 3.06 ERA in 45 starts since the start of the 2024 campaign. Again, he doesn't get much recognition, but he's been a consistently reliable workhorse for a while now. In fact, since he made his 2024 season debut on May 29, I'd argue he's been a top 10 pitcher in the National League. Here are his ranks among qualified pitchers in that span.

He's not going to go seven shutout innings with 10+ strikeouts often, but what he will do consistently is put his team in a position to win the game at hand. I don't think he has near the upside as most, if not every starter on this list, but his consistency can't be overlooked. He's the ace of the Mets' staff, and it's hard to envision them making the playoffs, let alone go on the run they hope to, without Peterson pitching well down the stretch.

9) Freddy Peralta, Milwaukee Brewers

Freddy Peralta has been rock-solid for a while for the Milwaukee Brewers, but it feels like this season has been the year in which he's taken the leap from solid pitcher to ace. The right-hander leads the majors with 15 wins and 27 starts, and in those appearances, he's pitched to a 2.68 ERA in 147.2 innings and has struck out over a batter an inning.

What's really stood out this season about Peralta has been his consistency. He's allowed one earned run or fewer in 15 of his 27 appearances, putting Milwaukee in a perfect chance to win more than half the time. In those other 12 starts, he's allowed three earned runs or fewer nine times. He's had three starts that can be classified as "subpar," but for the most part, Peralta has been as good as it gets in the NL.

He might not be as big of a name as Jacob Misiorowski, but he's the clear ace of this staff in 2025, and he honestly could be ranked higher on this list. What holds him back for me is that he's surpassed six innings just once all year, and his recent postseason track record (7 ER allowed in 9 IP across his last two postseason starts) is far from stellar.

8) Michael King, San Diego Padres

The San Diego Padres are just 1.0 game back of the Los Angeles Dodgers in the NL West which is impressive especially when considering the fact that their ace, Michael King, has been limited to just 11 starts this season due to injury. In those 11 starts, though, King has pitched like the All-Star-caliber arm he was in 2024, posting a 2.81 ERA in 57.2 innings of work and striking out 65 batters compared to 19 walks.

What's impressive about King the most is how consistently reliable he is. He's allowed three earned runs or fewer in all 11 of his starts this season, and he did this in all but five of his 31 appearances in 2024. He's new-ish to the starting rotation, but all he does is give his team a chance to win games. With the best bullpen in the sport behind him, it's hard to envision the Padres losing many of his postseason starts.

While King is quite good, he's completed six innings just twice this season and has done so in just 17 of his 42 appearances with the Padres. Again, with this Padres bullpen San Diego doesn't need much more than five strong innings which he's more than capable of providing, but because completing six frames has proven to be a challenge, particularly this season, it's hard to rank King much higher than this.

7) Max Fried, New York Yankees

Max Fried is another guy who probably would've been higher on this list if it were made a couple of months ago, but his recent struggles are impossible to ignore. The southpaw began his New York Yankees career on fire and along the lines of the likes of Tarik Skubal and Garrett Crochet in the American League, but a 5.94 ERA in nine starts since the start of July is really hard to overlook.

I know that the blister concerns have been there, and perhaps that's the explanation for his struggles, but I need to see him revert to form before putting him any higher. His last start was a very good start towards that.

What puts the cherry on top on Fried not being ranked quite as highly as some of the best pitchers in the game is his postseason resume. Fried made some big-time appearances for the Braves in October, but he also has a 5.10 postseason ERA across 20 appearances (12 starts), and has struggled mightily in each of his last three October appearances. Yankees fans hope this will change this season, and it better if they want to go on a deep postseason run.

Fried's regular season resume speaks for itself, but his recent struggles for the Yankees and his long-documented postseason struggles have him lower than Yankees fans might like.

6) Yoshinobu Yamamoto, Los Angeles Dodgers

It feels like he doesn't get much attention, which is certainly strange considering he's a Japanese pitcher on the Los Angeles Dodgers making over $300 million, but Yoshinobu Yamamoto has been as advertised in the majors. The right-hander had a 3.00 ERA in 18 regular season appearances in 2024, and when he's been needed to pitch like an ace this season, he's done that and then some.

The 27-year-old has a 2.90 ERA in 25 starts and 139.2 innings of work overall, making seven more starts and throwing 35 more innings than anyone on his team. The Dodgers have been riddled with injuries, particularly in their rotation, but Yamamoto has been both healthy and dominant this season. He's also been quite good against teams currently in postseason positioning.

He had clunkers against the Yankees and Brewers, but for the most part, when the challenge calls for Yamamoto to step up, he's done just that. The Dodgers don't come close to winning the division without him, and they should feel confident with him as their Game 1 starter.

5) Cristopher Sanchez, Philadelphia Phillies

Losing Wheeler stinks, obviously, but even without him, the Phillies have a bonafide ace of their own in Cristopher Sanchez. It's unfortunate Wheeler has to miss the remainder of the season, but now, it feels like the MLB world will come to learn just how good Sanchez is. He's been rock-solid for a couple of years now, but he's now one of the best pitchers in the National League.

The southpaw has a 2.66 ERA in 26 starts and 162.1 innings of work this season. He isn't as big of a name as several other NL aces, but who, outside of Paul Skenes, that is currently healthy, would you like to start a postseason game right now? Here's a look at where Sanchez ranks among all qualified NL hurlers in several key statistics.

Most of the pitchers ahead of Sanchez in these key statistics this season are not on teams in the playoff race. With Wheeler out, Sanchez might end up as the NL Cy Young runner-up to Skenes. Yes, he needs to figure out how to pitch a bit better on the road, particularly at Citi Field, but he's as good as it gets.

4) Bryan Woo, Seattle Mariners

Bryan Woo has made 25 starts this season for the Seattle Mariners, and he's gone at least six innings 25 times. No, that's not a typo. He's completed six or more frames each time he's taken the ball, and he's been the ace of this talented Mariners staff. He should be their Game 1 starter in October, and he's as good as it gets when compared to the rest of the league.

It's not as if the Mariners are just forcing Woo to complete six innings each time he starts. He has a sub-3.00 ERA, has struck out over a batter per inning, has a sub-1.000 WHIP, and he leads the majors in quality starts.

I'm not here to say Woo should be the AL Cy Young favorite, but his consistency and reliability cannot be overlooked. There aren't many pitchers you should trust to give you a quality start in October over Woo, and he should be considered one of MLB's premier aces.

3) Hunter Brown, Houston Astros

Honestly, I wouldn't be overly shocked if the Houston Astros gave Framber Valdez a Game 1 start in October. Valdez has been the ace of their staff for years, he was their Opening Day starter this year, and he's still a bonafide frontline starter. With that being said, Hunter Brown is the best pitcher the Astros have to offer, and he deserves the Game 1 start in October.

Brown has been overlooked in the AL Cy Young race, but he has a 2.36 ERA in 25 starts and 149 innings of work. He's been nothing short of dominant all season long, and that's really been the case since early May of last season.

Brown has only gotten better since his breakout last season, and this has particularly been true against winning teams. In 11 starts against teams at or above .500 this season, Brown has posted a 1.35 ERA in 66.2 innings of work. It's nearly impossible to be better than he has against the best, and that should give Astros fans the utmost confidence that he'll dominant in October.

2) Garrett Crochet, Boston Red Sox

If anyone was wondering whether Garrett Crochet was going to be a one-year wonder or if the Boston Red Sox gave up too much to acquire him, they no longer feel this way. Crochet has proven he's legit, and is arguably the best pitcher in the game right now.

The southpaw has a 2.38 ERA in 26 starts and a league-leading 166.1 innings of work this season. If Tarik Skubal didn't exist, he'd be the runaway favorite for the AL Cy Young award. Even with Skubal in the mix, he might end up winning the award anyway.

There were understandable concerns regarding his durability and whether he'd last a full season, but again, he's squashed all of those concerns emphatically. The southpaw has gone at least six innings in all but seven of his 26 starts, and he's allowed two earned runs or fewer in all but four of those outings. We've known the stuff is as good as anyone's, but we didn't see this level of consistency regarding going deep into games or dominance. It feels like he puts up ace-like performances every fifth day, which is increasingly well nowadays.

With that being said, Crochet is not Tarik Skubal.

1) Tarik Skubal, Detroit Tigers

Crochet is great, and I wouldn't blame you too much if you'd rather have him over Detroit Tigers ace Tarik Skubal, but Skubal has been marginally better this season and has a longer track record of ace-like production. Remember, he was the AL Cy Young award winner last season too.

Admittedly, some of these margins are razor thin, but Skubal leads Crochet in every key statistic other than innings pitched, and even then, he's just one out behind him. What really sets Skubal apart is his 6.1 fWAR and his 0.87 WHIP.

Even with his ridiculous stuff, Skubal's command is what makes him must-see TV. He leads the league with 212 strikeouts, but he's issued a total of 25 walks all season. How often do you see a guy lead the league in K/9 (11.5) but also BB/9 (1.4)? Skubal has 10 double-digit strikeout games and has issued a total of three walks in those outings. It's absurd.

Paul Skenes and Zack Wheeler would join Crochet in the running against Skubal if they were all healthy and in postseason contention, but there's nobody I'd take than Skubal right now. He was the best pitcher on the planet last season, and certainly looks the part in 2025 as well.