Michael O’Neill joined Triple-A San Antonio on May 26 when the Missions were short on outfielders.
Through eight games, O’Neill is hitting .240 with two RBIs.
The 26-year-old right-hander started the season in Double-A Biloxi, where he batted .290 with four home runs in 45 games.
This is O’Neill’s seventh season of pro baseball, all in the minors. He was drafted by the New York Yankees in 2013.
He spent most of last year in the Texas League, including playing against the then-Double-A Missions. He hit .255 with 12 home runs and 39 RBIs in 121 games for the Texas Rangers’ farm club in Frisco. He became a free agent at the end of the season.
O’Neill was signed by the Milwaukee Brewers to a minor league contract on March 9.