A's send down struggling starter Vin Mazzaro

In a surprising September move, the Oakland Athletics have optioned struggling starter Vin Mazzaro to Triple-A Sacramento.

Rosters expand in September, so the A's could have chosen to sit Mazzaro and have him work things out in side sessions and bullpens. Instead, Mazzaro was sent down Monday and will pitch in the River Cats' rotation during the Pacific Coast League playoffs.

Oakland manager Bob Geren said overall consistency was Mazzaro's biggest problem and the A's need to see better command and more strikes from the right-hander.

Mazzaro went 0-6 with a 5.60 ERA in his last eight starts during a second stint in the majors this year. He has dropped his last three starts, including Sunday's 7-4 loss to the Los Angeles Angels.