In other news, right-hander Kelvim Escobar will have shoulder surgery Wednesday and miss the entire season.
Pelfrey reported stiffness in the shoulder during his start Saturday in Philadelphia, where he lost 10-0 to Roy Halladay. Mets manager Jerry Manuel said Monday that Pelfrey is expected to follow his normal between-starts routine and pitch again next weekend at home against San Francisco.
Arm injuries have limited Escobar to one major league appearance since 2007. Still, the Mets signed him to a $1.25 million, one-year contract in the offseason, hoping he could be a late-inning reliever.
Escobar developed a sore shoulder in March, preventing him from pitching, and it hasn't improved.