Could Cade Horton Rejoin the Cubs for Game 5? Here’s What Would Have to Happen

The Cubs knotted up the NLDS on Thursday night and are now headed for a winner-take-all Game 5 in Milwaukee — and there’s one name fans keep whispering about: Cade Horton.

The 23-year-old rookie right-hander, one of Chicago’s most electric young arms, was left off the NLDS roster after suffering a rib fracture late in the regular season. It was a devastating blow considering how dominant he had been in the second half of the regular season (

Horton spent the past two weeks rehabbing, throwing bullpens, and is now ready to help his team in October.

“At this moment, I am pain-free,” said Horton earlier this week

So now that Horton’s healthy… can the Cubs just slot him back to start a deciding game? Not quite.

The Locked Roster Rule

Once the postseason roster is set for a given series, it’s essentially frozen. Teams can’t freely make swaps just because a player gets healthy or a manager wants a new look.

The only exception is an injury replacement — and even then, MLB has to approve it.

That means the Cubs can’t activate Horton unless one of their current pitchers on the NLDS roster suffers an injury serious enough to warrant removal. If that happens, the team would need to petition the Commissioner’s Office to replace the injured arm with Horton, and MLB would have to sign off before first pitch.

In other words: unless a Cubs pitcher goes down between now and Game 5, Horton has to watch from the dugout.

Even if that scenario plays out, postseason rules are strict about positional swaps — a pitcher can only replace another pitcher. And once the change is made, the replaced player is out for the rest of the series and possibly ineligible for the next round if the Cubs advance.

That’s the tradeoff. You can bring in a fresh arm, but you’re permanently losing someone else.

That makes it unlikely the cubs will fake an injury to get Horton activated. A move like that is unlikely to get approved by the league anyways. 

Horton would be the ideal option to start Game 5. Shota Imanaga has really struggled down the stretch in 2025 and got lit up in Game 2. But again, the Cubs may have no other choice since there’s no injury creating that opening.

Timing Matters

Any roster substitution must be finalized before the next game begins. So, if the Cubs wanted to get Horton eligible for a potential Game 5, the paperwork would need to be filed and approved by MLB prior to the first pitch.

That’s why these things often happen overnight or the morning of an elimination game — quietly, quickly, and usually out of necessity.

Reality Check

Craig Counsell and the Cubs have been careful not to promise anything on Horton. The organization made it clear that unless there’s a legitimate injury replacement, Horton will remain off the NLDS roster.

That’s frustrating, sure, especially for fans who see him as the team’s best chance of survival. But these are the rules, and they exist to keep teams from gaming the system.

So for now, Horton’s biggest contribution might be the energy he brings to the clubhouse and bullpen sessions — a reminder that even though he’s not throwing pitches in this series, the Cubs’ pitching future looks plenty bright.