cells to repair the damaged tissues in his right shoulder. The orthopedic surgeon who performed the surgery said he had used human growth hormone in previous surgeries of the same type but not with Colón. The surgery was scrutinized by Major League Baseball but no wrongdoing was found. Colón then played in the Pre-World Championship in Puerto Rico, winter ball with the Aguilas and the Leones del Escogido, and the Puerto Rican winter league., and announced that he would attempt a comeback to the major leagues for the 2011 season. He signed a minor league deal with the New York Yankees on January 26, 2011. Colón was invited to spring training, competing for a spot on the 25-man roster, despite coming into camp 30 pounds overweight. He was named to the Yankees' Opening Day roster in the bullpen. Colón made his first start for the Yankees on April 20, taking the rotation spot of the injured Phil Hughes. Through May, Colon was 3–3 with a 3.26 earned run average. On May 30, 2011, he threw a four-hit shutout, his first since 2006 against the Athletics. He sustained a hamstring injury on June 11, 2011, against the Cleveland Indians. When he was injured, he was in the seventh inning of a shutout game, but he limped off the field after covering first base on a ground ball to Yankees first baseman Mark Teixeira. Colón then ended up on the 15-day disabled list. He said that he'd be back pitching right when eligible. On July 2, Colón returned to the Yankees and threw six shutout innings against the New York Mets. On July 14 against the Blue Jays, Colón exited after recording only two outs in the first inning while yielding eight runs, the shortest outing of his career. Colón's 2011 season was somewhat of a resurgence, going 8–10 with a 4.00 earned run average and a 1.29 walks plus hits divided by innings pitched ratio. He was demoted to the bullpen when the Yankees made the postseason and the team lost to the Detroit Tigers in the 2011 ALDS. Oakland Athletics On January 14, 2012, Colón agreed to a one-year, $2 million contract with the Oakland Athletics. He started the second game of the season for the Athletics in the Opening Series in Tokyo, Japan, throwing eight innings, giving up one run over three hits while recording six strikeouts. On April