The Oakland A's have placed Michael Wuertz on the 15-day DL with tendinitis in his right thumb, CSNBayArea.com reports.

Wuertz had a 4.88 ERA with a .239 Opponents batting average in 34 games for the A's this season. He had a great first half with a 2.67 ERA while holding opposing batters to a sub-.200 average, but has struggled mightily in the second half. He has allowed nine runs on nine hits with eight walks in 4.1 innings since the All-Star break while posting an ERA of above 18 with a .450 opponents average. Wuertz also sat out in April with a hamstring injury.

Jerry Blevins will get the call-up to replace Wuertz. Blevins has been called up for the fourth time this season. He is 2-0 with a 5.01 ERA in 20 games for the Sacramento RiverCats.