The righthander pitched the ninth inning at Petco Park in San Diego against the Miami Marlins. Mikolas (MY-koh-lahs), 23, becomes the 109th former Fort Wayne star to reach the major leagues.
Mikolas appeared in 60 games for Fort Wayne, all in relief, in 2010 and worked to a 6-13 record with 13 saves and a 2.20 ERA. In 81 2/3 innings, he struck out 78 and walked 15.
Mikolas' contract was selected Saturday from Double-A San Antonio,where he 1-1 with a 2.92 ERA this season.