J.A. Happ wasn't able to start for the Phillies on Monday against the Astros because of a strained side muscle. Veteran Jamie Moyer made the start. "I felt something and it hasn't gone away," Happ said of hurting himself while taking batting practice over the weekend. The rookie, who is 10-4 with a 2.77 ERA, expects to make his next start this weekend. "I've had this before and it's one of those things where they have a way of being unpredictable and lingering," Happ added. "We're trying to take the right approach here and knock it out before it gets worse."