The A's optioned struggling right-hander Jesse Hahn to Triple-A Nashville and recalled right-hander Zach Neal and infielder Max Muncy from Triple-A on Friday.
Hahn had a 6.49 ERA in seven starts for Oakland this season. In his last two starts he allowed a total of 11 runs in just 4 1/3 innings.
Neal, a rookie, has pitched in three games in two brief stints with the big league club this season, including one start. He has an 11.25 ERA.
Muncy was previously recalled on May 17 and went 2-for-5 in two games for the A's, his only Major League stint this year, before being optioned back to Nashville. He was batting .263 with seven home runs and 20 RBIs in 44 games at Triple-A.