The Phillies hurler, en route to a return to the major leagues after spending the first chunk of 2009 working out independently in the Dominican Republic, threw a 53-pitch bullpen session over the weekend to smooth out his stretch delivery.
Martinez — who allowed four runs in five innings during his last rehab start in Triple-A — told ESPN.com his issues were ironed out.
"I struggled the last time only from the stretch," Martinez said. "So we wanted to specifically work on the pitches that I missed in the stretch. Like I said before, I thought it was something that could be quickly corrected. I hope I can put it into play soon."
There is still no timetable set for Martinez's return to the big club, especially considering Philadelphia's recent addition of Cliff Lee. Lee is one of four lefties in the Phillies' current rotation, joining Cole Hamels, Jamie Moyer and J.A. Happ.
Philadelphia general manager Ruben Amaro Jr. told ESPN.com he, too, is unsure of when Martinez's debut will happen.
"We don't have a current plan as of yet what the next step is other than he'll throw a bullpen [session Sunday]," he said last week. "Once we talk to Pedro about the plan, we'll let you know."
The 37-year-old will make his next start on Wednesday at Double-A Reading.
