Jon Niese has gone from Opening Day starter to almost the Mets’ forgotten man.

But the lefty might look familiar to teammates today when he is scheduled to make his first start since going on the disabled list with a partially torn left rotator cuff on June 21.

Niese who is 3-6 with a 4.32 ERA likely will be limited to 90-95 pitches against the Diamondbacks.

“I think it’s important for Jon Niese mentally to know that his arm is OK” manager Terry Collins said before the Mets’ 4-1 victory over the Diamondbacks last night. “If he finishes [the year] strong he knows he’s back and will be strong with his reps over the wintertime.”

The Mets were without a lefty starter in Niese’s absence and Collins said it will be nice to have a different look in the rotation.

“Especially when you run Dillon Gee and [Jeremy] Hefner at the same team they’re such similar type of guys it’s nice to break up that pattern of having similar guys from one side throwing” Collins said. “That lefty breaks it up.”