Barnett will start Thursday's game against the Astros in Sacramento.
The Athletics summoned Barnett from Triple-A Las Vegas last Friday to make his first appearance for the big club in more than a month, and the 25-year-old right-hander languished in a 5-3 loss to the Guardians. He took a no-decision in the start, coughing up three runs on seven hits and four walks in 3.1 innings to bring his ERA and WHIP up to 7.16 and 1.75, respectively, over his 19 appearances for the Athletics on the season. Despite the poor showing, Barnett will receive one last turn through the rotation as the Athletics kick off a four-game set versus Houston to close out the campaign.