Isaiah J. Downing, USA Today Sports

Arizona Diamondbacks ace Zack Greinke was cruising on Wednesday against the Pittsburgh Pirates. But his outing was cut short with an apparent injury.

After he threw his 95th pitch of the game, Greinke called the trainers out (per Zach Buchanan, The Athletic) and was removed. It’s unclear where he was hurt. But he was in pretty obvious discomfort.

Buchanan also noted that Greinke appeared to suffer some discomfort in a previous at-bat.

Greinke had gone 7.2 innings shutout innings, surrendering only four hits and no walks while striking out five. He also drew a walk and stole a base.

This will be worth paying attention to in the coming days. An injury to Greinke would obviously severely hurt Arizona’s rotation.

Following Wednesday’s outing, he had a 2.78 ERA and 0.881 WHIP on the season.