Ambriz, signed as a minor league free agent on June 21, went 1-1 with a 3.33 ERA in 18 games with Oklahoma City. He had pitched in 20 games for the Cleveland Indians organization earlier this season before being signed Houston. Ambriz appeared in 34 games with Cleveland in 2010.
Galarraga was 0-4 with a 6.75 ERA in five starts with the Astros before being designated for assignment on Wednesday.
Copyright 2012 by The Associated Press
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