Pruitt, called from Triple-A Las Vegas earlier in the day, fired three scoreless innings during which he allowed two hits in a loss to the Rangers on Saturday.
Pruitt gave the Athletics some much-needed length on a day when starter Zach Logue was chased after 2.1 innings. The journeyman right-hander, who also has 10 starts on his career resume, is likely to remain in a multi-inning role while up with the big-league club.