Detroit said Martinez has left knee inflammation. He had surgery on that knee in February after tearing the medial meniscus.
"We had a plan back in April. It hasn't worked out," Detroit manager Brad Ausmus said. "He had a cortisone shot last Thursday, and we gave him three days off. He played [Monday]. At this point, we felt other steps were necessary. It wasn't working. ... There's a weakness created by the surgery. It's created an issue in another part of the knee."
Martinez, 36, is hitting .216 with only one home run. The switch-hitter is 12-for-26 (.462) against left-handers and 12-for-85 (.141) against righties.
"We're just not seeing the real Victor. We're seeing a shell of what Victor is," Ausmus said. "We told him not to pick up a bat for about a week."
Detroit has four outfielders who have been in the starting lineup for at least 14 games: Yoenis Cespedes, Anthony Gose, J.D. Martinez and Rajai Davis. Now they all might play regularly, since Martinez's designated hitter spot is open.
Outfielder Tyler Collins was recalled from Triple-A Toledo to fill Martinez's roster place.
Tigers place Martinez on 15-day DL
Jayson Stark discusses the Tigers' decision to place Victor Martinez on the disabled list and their plan to shut him down until his knee fully recovers from the surgery he had in February.