"When he saw the changeup," Martinez said with a giggle, "he told me that was the one he used to swing at all the time."
The 55-pitch session was only a small first step toward Martinez pitching for the Phillies. He'll join Class-A Clearwater on Monday and likely make at least a few starts in the minors before returning to the majors.
Even then, he's not counting on cracking Philadelphia's rotation.
"I would just like to be the backup," the three-time Cy Young Award winner 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?"
The 37-year-old Martinez, who finalized a $1 million, one-year contract with the Phillies on Wednesday, hasn't pitched since September and won only eight of 25 starts the past two seasons with the New York Mets.
Phillies pitching coach Rich Dubee declined to say what Martinez's schedule will be next week.
"We're taking it day by day," Dubee said. "We'll see how he feels and go from there. We have no major plan mapped out."
After signing Martinez, the Phils placed him on the 15-day disabled list with a shoulder strain, and he's not eligible to be activated until July 31. The right-hander said his shoulder's sore, but he threw all of his pitches in the bullpen session.
"It went better than I thought," he said after throwing for the first time in eight days. "As far as command and pitches, I felt pretty comfortable."
Martinez is with the Phillies for this weekend's series against Florida. They went into Saturday night's game with a seven-game winning streak and a six-game lead in the NL East.
"Since I've been here, I've just got the feeling we're going to win every day," Martinez said. "This team is so relaxed and so confident."