An MRI of New York Mets left-hander Jonathon Niese's pitching shoulder has come back "clean," and the southpaw will resume throwing within a couple of days, manager Terry Collins said. Niese had been dispatched to the Hospital for Special Surgery in Manhattan on Wednesday after complaining of shoulder discomfort. He told before departing that the exam primarily was for peace of mind, since he missed two months of last season with a partially torn rotator cuff. Collins indicated the only issue is some "weakness" with the scapula, in the back of the shoulder. Still, Niese will be permitted to resume throwing this weekend. He will not make his first scheduled Grapefruit League start, though, which had been slated for Tuesday against the Houston Astros. The Mets continue to plan for Niese to start on Opening Day, March 31 against the Washington Nationals at Citi Field. The club has Bartolo Colon lined up for the second game of the season, followed by Dillon Gee in Game 3. Zack Wheeler is then due to open the second series, against the Cincinnati Reds.