Taking stock of New York's rotation configuration with support incoming

NEW YORK -- The Mets’ rotation will soon start evolving.

It won’t happen this week, or even this month. But changes are coming to the best rotation in baseball -- a unit that, even after Clay Holmes uncharacteristically allowed two homers in a 4-0 loss to the Pirates on Wednesday night, still leads the Majors with a 2.74 ERA.

The quintet of Holmes, Tylor Megill, Griffin Canning, David Peterson and Kodai Senga have started 41 of the Mets’ first 44 games and, barring injury, should remain as currently constituted until at least the first week of June. At that point, facing a stretch of 10 consecutive games without an off-day, the Mets may again look to insert an extra pitcher as they’ve done on three occasions already: first with bulk relievers Justin Hagenman and Brandon Waddell, then with rookie starter Blade Tidwell.

Beyond that, even more change is inevitable. The only question is when.

Getting healthy

The most obvious future rotation alterations involve Frankie Montas and Sean Manaea, two pitchers who entered Spring Training penciled onto the Opening Day roster. Montas strained his right lat early in camp and has been sidelined ever since. Manaea subsequently pulled his right oblique and suffered a setback during his recovery.

Both are still on the mend, with Montas tiptoeing closer to a Minor League rehab assignment and Manaea beginning to throw off a mound. Both should return in June.

At that point, the Mets will have options. They could, for example, move permanently to a six-man rotation. They could bump someone to Triple-A Syracuse (though no Mets starter has pitched poorly enough to warrant that right now). At this point, it’s not even worth speculating on the roster puzzle, because injuries and circumstances can change so quickly. These things tend to work themselves out.

Nonetheless, it’s clear that once Montas and Manaea are right, they will play significant roles.

Don’t the Mets have another injured starter?

As a matter of fact, they do. Paul Blackburn is set to stretch out to around 75 pitches Friday for Double-A Binghamton, with one more rehab start to follow. Despite not having an obvious rotation spot up for grabs, team officials want Blackburn to stretch out to a full starter’s workload while he’s rehabbing from a bout of right knee inflammation. Their logic is simple: if the Mets don’t do so now, it’ll be much more difficult to do so later, on the fly.

If Montas isn’t ready by the first week of June, Blackburn would be a perfect candidate to serve as a temporary sixth starter at that time. Otherwise, Blackburn, who is out of Minor League options, can be a long man out of the bullpen.

What about the farm system?

The Mets already debuted one of their brightest young pitching prospects, Tidwell, for a spot start earlier this month. Although that cameo didn’t go swimmingly, Tidwell remains part of the future and could return soon.

Top-ranked pitching prospect Brandon Sproat, meanwhile, continues to produce uneven results at Syracuse, following two solid outings with a six-run clunker on Wednesday. Mets officials would prefer to promote Sproat once they know they can give him a long runway of starts, but that’s unlikely to happen until the right-hander proves more consistent. The team is willing to be patient with him.

Perhaps most intriguing is fifth-ranked prospect Nolan McLean, who recently earned a promotion to Syracuse and debuted at that level with seven shutout innings. More than one scout who watched the Mets this spring preferred McLean over Sproat as the team’s most promising long-term pitching prospect. McLean is less than a year younger than Sproat, so it wouldn’t be shocking for him to leapfrog his teammate on the organizational depth chart. But team officials aren’t looking that far down the road right now.

“I’m not going to start getting into timelines to Major League arrival quite yet,” president of baseball operations David Stearns said of McLean. “I think we’re going to let him perform at Triple-A. His first start was great. That was great to see. And I look forward to watching him continue that.”