Pedro Martinez threw his first bullpen session as a member of the Phillies on Saturday. He did so with new teammate Matt Stairs standing at the plate, throwing about 55 pitches in the first step towards his first official appearance with the defending champions. Martinez admitted that he isn't even aiming to join the team's rotation. "I would just like to be the backup," he said. "If I could be the backup, that would be a great thing to have?a healthy Pedro behind everybody else in case something happens. That would be a great feeling to have on a team, eh?" After signing Martinez, the Phillies placed him on the 15-day disabled list with a shoulder strain, and he's not eligible to be activated until July 31.