The Pittsburgh Post-Gazette reports that the Pirates will send Andrew McCutchen to the 15-day disabled list with an oblique strain.
The reigning NL MVP strained his oblique muscle while hitting a sacrifice fly in Arizona on Sunday. He held his side and needed help exiting the field and descending the steps into the visitor's dugout.
The night before, McCutchen was visibly angry after Arizona reliever Randall Delgado beaned him in the back.
The Pirates could be without their star center fielder for three weeks to a month, dealing a blow to their hopes of making the playoffs two years in a row.
Starling Marte could fill in for McCutchen in center field once he's cleared to return from the seven-day concussion disabled list.
McCutchen's offensive production will be hard to replicate. He's managed to surpass last year's numbers and put himself back in the MVP conversation, hitting .311 with 67 RBIs, 17 homers and a .947 OPS.
The Pirates are a half-game back from the second wild-card spot and trail the Brewers by 1 1/2 games in the NL Central.