CHICAGO -- An MRI taken of Eric Chavez's side showed a minor tear of his right oblique muscle.
Chavez sustained the injury while taking a swing in the first inning of Thursday's game against the Rangers.
The team placed Chavez on the 15-day disabled list Friday, and it is uncertain how long he will be out.
"The best-case scenario would probably be 15 days to three weeks," D-backs manager Kirk Gibson said. "It's hard to tell. I've had those where you get them and you go down and you can't breathe. It wasn't like that, but it was definitely there."
D-backs shortstop Willie Bloomquist suffered an oblique tear towards the end of Spring Training and was activated for the first time on Friday.
"It doesn't look like it's as bad as Willie's," Gibson said.
Chavez was a big part of the Arizona offense hitting .325 with seven homers and 25 RBIs before the injury.