Pedro Martinez appears ready to return to the Mets' rotation at the end of next week. In his attempt to return from a strained right calf, Martinez threw a simulated game off the Shea Stadium mound prior to Saturday's game against the Dodgers. Martinez tossed 75 pitches and, according to a team official, "about four innings" of live action with Mike DiFelice catching and Anderson Hernandez, Ricky Ledee and Lastings Milledge taking at-bats. Manager Willie Randolph, pitching coach Rick Peterson and bullpen coach Guy Conti observed Martinez from behind a screen set up behind the mound, and DiFelice called balls and strikes. Martinez worked each inning as if it were a live game, sitting down between frames.