Jameson Taillon's return lasted barely a start, and now he's facing an MRI tonight.

John Schneider said the right-hander is likely headed back to the IL, just hours after being activated to start.

That's a brutal turn for a pitcher who'd cleared every checkpoint in his forearm rehab without a setback.

Schneider said Taillon reported that the discomfort in his elbow felt different this time compared to his previous injury.

That distinction matters. A different sensation than before suggests this may not simply be a flare-up of the same issue.

The MRI tonight should provide real clarity on what the club is actually dealing with.

In the meantime, Toronto is already planning around his likely absence, debating whether to use a bullpen arm or stretch someone out for length tomorrow.

Why this setback hits especially hard right now

Taillon had just been reinstated from the 15-day IL, with Ricky Tiedemann optioned to Triple-A to clear his roster spot.

That corresponding move may need to be revisited depending on what the MRI shows and how Toronto decides to fill the rotation spot.

The timing could not be worse. Toronto sits right on the edge of a wild-card spot, in the middle of a stretch where every healthy arm matters.

This rotation has already absorbed injuries to Jose Berrios, Bowden Francis, Patrick Corbin, Trey Yesavage, and Shane Bieber this season.

Adding Taillon back to that list, especially with a potentially new elbow issue, would be a significant blow to a staff already running on fumes.

There's no diagnosis yet, and Schneider's cautious tone reflects genuine uncertainty rather than a settled outcome.

Whether tonight's MRI reveals something serious or a more manageable issue will shape how Toronto approaches its rotation for the rest of this playoff push.