Niese had a favorable follow-up exam with team doctor David Altchek at the Hospital for Special Surgery in Manhattan on Monday and has been cleared to head to the team's complex in Port St. Lucie, Fla., to begin throwing, assistant general manager John Ricco said.
Niese had landed on the DL after a June 20 start with what was announced as a partial strain of the rotator cuff in his left shoulder.
At the time, the team said Niese would have a follow-up MRI two weeks later to determine if healing had occurred, or if surgery might be necessary. Monday's reexamination worked out favorably for Niese.
"There's some normal wear and tear in there that a pitcher would show, but nothing that [Altchek] termed as any kind of a new injury," Ricco said. "All pitchers have something in there. So I think that's what they were seeing. But now on the clearer MRI he said he was really happy.
"The other part of it is Jon is asymptomatic on all of his tests, so he's feeling great and looking forward to getting going again."
Ricco said the timetable for Niese to get back into a major league game is unclear, but it will be a process because Niese has not thrown a baseball for more than two weeks.
"Until he gets down there and starts long-tossing, we won't know," Ricco said.
At the time Niese landed on the DL, the Mets had an excess starter, since rookie Zack Wheeler had been promoted from Triple-A Las Vegas and no one had been bounced from the rotation. Since then, however, right-hander Shaun Marcum has redeveloped tingling and numbness in his cold right hand. Marcum was examined Monday by doctor Robert Thompson at Barnes-Jewish Hospital in St. Louis.
Thompson is the same doctor who performed surgery on right-hander Dillon Gee last July for a blood clot in his shoulder that was causing hand numbness.
"Dr. Thompson is one of the top guys in the country," Ricco said. "We were in Milwaukee, so we were close. It's close to Shaun's home. It's something he was comfortable with."
The Mets have summoned reliever Gonzalez Germen from Las Vegas, although Ricco said he would not be active until Tuesday at the earliest. Summoning Germen signals Marcum will be placed on the disabled list, since the rookie has not been in the minors for 10 days since his last demotion and therefore could not otherwise return.