Outfielder Jake Marisnick was recalled from Triple-A New Orleans to fill Dietrich's roster spot.
Dietrich last played on Tuesday and went hitless in four at-bats against the Phillies. The left-handed-hitting infielder felt some discomfort taking a practice swing while on deck. He stayed in the game, but on Wednesday in the batting cage, the wrist bothered him enough to get an MRI exam, which revealed the strain.
"While in the on-deck circle taking a practice swing, he felt something," manager Mike Redmond said. "The next day, he said swinging in the cage, he took quite a few swings and it blew up on him. He got it checked out. Had an MRI, and we put him on the DL."
Dietrich opened the season as the Marlins' starting second baseman. He was optioned to Triple-A New Orleans on June 3, shortly before Rafael Furcal came off the DL. But when Furcal was placed on the DL on June 22 with a left hamstring strain, Dietrich was called back up.
Since returning, Dietrich is 4-for-28 (.143) with one double and an RBI.
For the season, Dietrich is hitting .228 with a .326 on-base percentage, with six doubles, two triples, five home runs and 17 RBIs. He's had his struggles defensively, committing 10 errors at second base, and one error at third.
Donovan Solano and Ed Lucas have been handling second base of late.
The Marlins hope to get shortstop Adeiny Hechavarria back on Monday for the series opener at Arizona.
Hechavarria (right triceps strain) went on the DL on June 25, retroactive to June 21.
The plan is for Hechavarria to play two rehab-assignment games for Class A Jupiter on Friday and Saturday, and travel to Arizona on Sunday. Barring a setback, he should be reinstated on Monday.