Yankees GM Brian Cashman is aggressively trying to upgrade his starting staff, which has seen four-fifths of its opening day rotation end up on the disabled list.

"I have to reinforce our pitching, in my opinion," Cashman said in a phone conversation Thursday. "I have things that I feel I have to try to do, that I'm trying to do, but it is easier said than done."

Cashman is in go-for-it mode, even though the Yankees, 47-47 on the season, start the second half five games behind the Baltimore Orioles in the AL East and 3½ back of the Seattle Mariners for the final wild card.

The Yankees' starting rotation has lost Ivan Nova and CC Sabathia for the season. Michael Pineda and Masahiro Tanaka are both on the disabled list. Both could possibly return in August.

The Yankees' second-half rotation consists of Hiroki Kuroda, rookie Shane Greene, David Phelps, Brandon McCarthy and Chase Whitley.