The Red Sox have placed pitcher Daisuke Matsuzaka on the disabled list with tightness in his right forearm. He was a late scratch for his scheduled start against the Phillies on Saturday. "Primarily, we're not going to throw a starting pitcher with forearm tightness in his next start or two out of caution," general manager Theo Epstein told ESPNBoston.com in an e-mail after the game.