After Barnett's struggles in the A's rotation last month he was optioned to Triple-A. In his most recent outing he tossed a gem — then a spot opened up in the rotation.
Earlier this week, the A's placed left-handed starter Gage Jump on the IL, ending his season. His rotation spot comes up today, Friday, and the A's have officially added Mason Barnett to the roster to take his spot in the rotation. Left-handed relief pitcher Joe Rock has been optioned to Triple-A Las Vegas as the corresponding move.
Barnett has been up and down with the Athletics this season, and even made four starts from July 30 to August 17. As a starter he holds a 10.69 ERA this season across 16 innings, giving up a .318 batting average against in the process. In his final three starts for the A's, he was unable to complete five innings in any of them, and gave up at least five runs in each, ballooning his season ERA to 7.08.
In his most recent start with the Aviators on September 12, Barnett tossed a complete game, giving up two earned runs on six hits and two walks, while striking out six. It was his first time throwing at least seven innings since September 10, 2024, when he was with the Double-A Midland RockHounds, shortly after joining the A's via trade.
Barnett had a strong stretch for the A's out of the bullpen back in June, going 1-0 with a 1.35 ERA and a 0.90 WHIP across 13 ⅓ innings of work. He also earned a pair of saves in that span in two opportunities.
Barnett's start on Friday will come against the Cleveland Guardians, who are attempting to make the postseason either as the winners of the AL Central, or as the final American League Wild Card. The Chicago White Sox's win on Thursday vaulted them into a tie with Cleveland, and the Sox hold the tiebreaker.
Cleveland has a two-game lead in the wild-card race over both the Toronto Blue Jays and the Texas Rangers.
Joe Rock was claimed by the A's from the White Sox on August 16, and optioned to Triple-A Vegas. He was called up earlier this week when Jump landed on the IL to give the A's an extra bullpen arm.
Rock made his A's debut on Thursday against the Tampa Bay Rays. He faced three batters and didn't record an out, giving up a hit and walking two, resulting in two earned runs before he was lifted in the sixth inning. Compounding the outing, he gave up three stolen bases in that time.
