The Houston Astros have been dealt a brutal blow, and fans didn’t even see it coming—literally.

Star shortstop Carlos Correa suffered a “significant injury” to his left ankle, according to MLB.com’s Brian McTaggart. The injury didn’t happen during a game or even on the field. It occurred while Correa was taking swings in the batting cage on Tuesday in Houston. The exact cause remains unclear, leaving an unusual element of mystery around the setback.

McTaggart reports that Correa could be sidelined for weeks—or possibly months. That’s a devastating timeline for a team already struggling to find its footing. The Astros entered Wednesday with a 15-22 record, and losing a veteran presence like Correa is the last thing they needed.

While Correa may not be the MVP-caliber player he once was, he’s still been a steady contributor this season, batting .279 with a .788 OPS. His absence will be felt both in the lineup and in the clubhouse.

The injury bug has been relentless for Houston. Catcher Yainer Diaz recently landed on the Injured List with a left oblique strain. The Astros are also without Jeremy Peña, along with outfielders Jake Meyers and Joey Loperfido. It’s a growing list that’s testing the team’s depth early in the season.

Sometimes, a season derails not because of a single bad play, but because of a cascade of unfortunate injuries. For Correa and the Astros, this latest one feels like a gut punch that came out of nowhere.