On March 31, Phillies GM Rubén Amaro, Jr. announced that Chan Ho Park had won the fifth starter job. However, with several poor starts (7 starts with a 7.29 ERA), Park was moved to the bullpen and was replaced in the rotation by J. A. Happ. The problem with Park as a starter was that he was sacrificing velocity and movement for the energy to go deeper in games. After moving to the pen, his four-seam fastball velocity returned to normal (topped out at 95-96 mph), with movement on his two-seam fastball and slider. Park played a vital role in the Phillies' bullpen with a 2.52 ERA. After missing time with a hamstring injury, Park made his return to the Phillies in the playoffs. With the Phillies, he advanced to his first World Series, in which he pitched well, giving up no runs in Philadelphia's loss to the New York Yankees. He became a free agent after the season.