Red Sox right-hander Daisuke Matsuzaka will make two more rehab starts for Triple-A Pawtucket before being called up to Boston's starting rotation. The pitcher had Tommy John surgery on his right elbow in June 2011, is scheduled to start for the PawSox on May 17 and May 22 before his rehab assignment expires on May 23. Matsuzaka made his fourth minor league start on Saturday in Pawtucket, working 5 1/3 innings. Red Sox manager Bobby Valentine watched the game tape of Matsuzaka's outing and it was clear to the manager that Matsuzaka needs some more time. "I didn't think he was as good as he should be," Valentine admitted. "His mechanics weren't very good at all. But he's throwing pain-free, so that's good." Matsuzaka had said after his third rehab start last week that he was not happy with his mechanics.