In the beginning of 2008 season, Matsuzaka led the Red Sox pitching staff with eight consecutive wins without suffering a single loss. However, on May 27, he left the game against the Seattle Mariners in the bottom of the fifth inning due to a "tired shoulder". The game resulted in a 4–3 loss. The Red Sox placed Matsuzaka on the disabled list May 30, 2008, with a mild right rotator cuff strain. He returned on June 21 but was the losing pitcher after giving up 7 earned runs in just one inning of work against the St. Louis Cardinals. Despite a record of 9–1 and a 3.12 ERA at the break, Matsuzaka was not selected to the 2008 American League All-Star team. On September 15 he won his 17th game of the season, setting a new single-season record for Japanese MLB pitchers, passing previous record holder Hideo Nomo.