Projected Cubs playoff rotation after devastating Cade Horton blow

The Chicago Cubs just suffered a critical blow in advance of the MLB Postseason, placing rookie ace Cade Horton on the 15-day IL due to a rib fracture. Viewed as a potential No. 1 starter in the playoffs, Horton could now miss multiple rounds, should the Cubs advance deep into October. He finishes his rookie campaign with a 2.67 ERA and 1.09 WHIP in 23 starts (118.0 innings).

Horton has undeniably benefitted from positive luck this season — his expected ERA sits at 3.94 — but Chicago's stellar defense carries its weight behind him and Horton has operated with tremendous poise for a 24-year-old just getting his feet wet. He's the odds-on favorite to win NL Rookie of the Year as a result. We can contest such a declaration, as Drake Baldwin has perhaps a stronger overall résumé, but when the Cubs' injury-battered rotation needed it most, Horton stepped up and delivered consistent, high-level results.

Chicago was already without headlining ace Justin Steele, who is recovering from elbow surgery, but Horton's absence leaves them even thinner. The National League already includes some of the absolute best rotations in MLB between the Dodgers, Phillies and Brewers, so the Cubs can ill-afford this decimation of an already-volatile group.

Still, the Cubs must press on, and it's not like Craig Counsell is completely devoid of quality options in Horton's absence. Here's who we might see take the mound for Chicago come October.

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Cubs projected postseason rotation without Cade Horton

This has been a somewhat underwhelming sophomore campaign for Shōta Imanaga, who made the All-Star team and looked the part of a headlining ace a year ago. Still, Imanaga can miss the meat of the bat with a nasty split-finger pitch and he throws his fastball with remarkable precision.

Both Imanaga and Matthew Boyd, who did make the All-Star team this season, limit walks and thus limit the potential for truly explosive innings, which is a valuable trait in the postseason. Both can give up some hard contact, Imanaga especially, but the Cubs' top two arms aren't easily rattled and tend to set up their defense for success. It could be a lot worse.

The depth beyond Imanaga and Boyd, however, is where Cubs fans will start to sweat. Horton would round out that trio perfectly. Instead, Chicago's third starter is probably 33-year-old Jameson Taillon. While Taillon has become increasingly solid since arriving on the North Side back in 2023, he's not everybody's favorite archetype when it comes to postseason pitching. Taillon pitches to contact, with a deep arsenal that prioritizes location control over punch-out stuff. That said, Taillon is another Cubs pitcher who keeps walks to a minimum, and he gets a lot of groundballs, which can play well with such a stout defense behind him. Taillon's pitches move around a lot.

Colin Rea is the fourth option, should Chicago push that deep. He can throw seven different pitches to keep a hitter off balance, but in all honesty, he'd be more of a long-relief option for most contenders this time of year. The Cubs would feel a lot more secure with Horton occupying this spot.

Javier Assad is another option, and he was excellent for long stretches in 2024, but he only recently returned from injury and has failed to leave a strong impression in seven appearances (six starts) this season. As a result, he's probably an emergency depth option or a long reliever when the Cubs find themselves in an early hole.