Steven Matz #32 of the New York Mets reacts after...

Steven Matz #32 of the New York Mets reacts after giving up a sixth run to the Atlanta Braves in the fifth inning before being pulled in the middle of the fifth inning at Turner Field on June 24, 2016 in Atlanta. Credit: Getty Images / Kevin C. Cox

LAKE BUENA VISTA, Fla. — Steven Matz’s last-ditch effort to get his aching left elbow ready for Opening Day ended with a trip to the doctor’s office for an MRI exam on Wednesday, leaving the Mets to choose between Seth Lugo and Zack Wheeler for the open spot in the starting rotation.

“It’s unlikely that Steven will start the season with us,” manager Terry Collins said after Wednesday’s Grapefruit League finale, a 2-2 tie with the Braves.

With the oft-injured starter back on the shelf, the Mets must make a decision that is rife with complications and special considerations. Either way, assistant general manager John Ricco said the intention is to make a call well ahead of when rosters must be set just before Monday’s Opening Day.

Elbow tightness prompted the Mets to scratch Matz, a Ward Melville product, from a scheduled start on Monday. Initial tests revealed no ligament damage. He instead threw off flat ground, then followed up Tuesday with a few pitches off a mound. But both times, Matz felt discomfort.

“The last two days he’s played catch and still feels it,” Collins said. “So, we thought it would be important to have him looked at.”

Now, the Mets must whittle down their options in the rotation, a decision loaded with what Ricco called “intertwined” factors such as long-term interest, short-term interest, health and overall development.

Lugo, 27, bailed out the Mets’ ravaged rotation late last season. He went 5-2 with a 2.67 in action as both a starter and reliever. He pitched well for Puerto Rico at the World Baseball Classic, bolstering his case.

But Wheeler, 26, has raised eyebrows in camp. After two years missed following Tommy John surgery, he has looked healthy, his fastball again roaring at 97 mph. It has been enough to vault him into the thick of the race.

Wheeler will have an innings limit. But despite a widely-reported range of roughly 120 innings, Ricco said there has been no hard and fast ceiling that has been implemented.

“There’s going to be some number but we don’t exactly know what that is,” Ricco said, noting that there is no science behind such limits, and that Wheeler has already reached 185 1⁄3 innings in 2014.

Ricco also raised the possibility of doctors re-evaluating Wheeler’s workload cap as the season progresses. Still, some kind of limit is in place, and the logistics of managing it is a consideration for the Mets.

“There’s no sleep chamber that you can put him in and then wake up in Mars,” Ricco said. “No matter what you do, there’s stuff that’s going to happen in the interim.”

The Mets also must guard against essentially wasting Wheeler’s finite amount of innings in the minors, especially if that work goes beyond rehab-type outings to prepare for big league action.

Lugo’s case was built late last season while Wheeler’s is based on what Ricco called “positive momentum.” But there is room for one, not both.

“The part you can’t undersell is the personalities,” Ricco said. “That’s maybe the most complex part of the puzzle.”