The Red Sox made Lester, 30, available after failing to sign him to a long-term contract extension. He was 10-7 with a 2.52 ERA at the time of the trade. Cespedes was in his third year with the A's after they signed him out of Cuba. His contract runs through 2015 and he's owed $10.5 million next season. An All-Star this season, Cespedes was hitting .256 with 17 home runs and 67 RBI when traded.