The A's injury epidemic continued Tuesday, as the team announced right-handed pitcher Daniel Gossett will undergo Tommy John surgery Wednesday to repair the ulnar collateral ligament in his right elbow. 

Gossett will become the fourth A's starter to go under the knife this season, joining Jharel Cotton, A.J. Puk, and Kendall Graveman.

"We've been hit hard with that this year," A's manager Bob Melvin said Tuesday. "It's unfortunate. These are injuries that keep you out for a while."

Gossett, 25, was 0-3 with a 5.18 ERA in five starts this season. He was originally placed on the DL June 5 with a right elbow flexor strain.

"He's a hard-working kid," Melvin said. "He's come a long way. We saw some really good games from him this year. I believe he'll rehab this thing and be back as strong as ever, but unfortunately it's going to take a while."

The A's have used 12 different starting pitchers this season, due to injuries. Despite that, they enter play Tuesday with a 62-46 record, just two games behind Seattle for the second AL Wild Card spot.