Tigers option Daniel Schlereth
Detroit allowed 30 runs in the first two games of the series, and with a day game on Thursday, manager Jim Leyland said the Tigers needed an extra arm in the bullpen.
Schlereth allowed two grand slams on Tuesday, and is 0-1 with a 4.29 ERA in 29 games.
Villarreal went 1-1 with a 6.46 ERA in 14 games with Detroit before being sent to Toledo in May.
Copyright 2011 by The Associated Press
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