WASHINGTON -- Following Monday evening’s 10-inning, 9-7 victory over the Nationals, manager Carlos Mendoza ended his postgame interview and immediately proceeded to his office, where his cell phone was located.

“Back to the phone,” Mendoza said ruefully, prepared to discuss some more pitching staff gymnastics.

With Edwin Díaz suspended, two other key relievers (Brooks Raley and Drew Smith) almost certainly out for the season and Sean Reid-Foley (1.66 ERA) on the IL with a right shoulder impingement and unlikely to return until after the All-Star break, the Mets have cycled through bullpen arms almost daily over the past week. That strategy continued Tuesday with one of their most intriguing moves yet, when the Mets recalled José Buttó from Triple-A Syracuse and placed him in the bullpen.

Team officials have been clear that they want to keep Buttó stretched out as a starter long-term, which, in pitching coach Jeremy Hefner’s estimation, means confining him to the bullpen for no longer than about 10 days.

But in the short-term, the Mets really, really needed a bullpen arm. They considered Buttó their best option.

“We see him as a starter, but he’s got that ability to help us out of the ‘pen as well,” Mendoza said. “That’s important, especially where we are now.”

With Díaz suspended, the Mets have relied on their bullpen for an average of more than 12 outs per night, cycling through relievers such as Ty Adcock, Matt Festa, Tyler Jay and Danny Young -- none of whom ranked highly on the depth chart heading into Spring Training. It hasn’t gone well, as the Mets have posted a 7.20 bullpen ERA over that stretch.

Enter Buttó, who has some prior experience pitching out of the bullpen. But Buttó has mostly thrived as a starting pitcher this season, producing a 3.08 ERA over seven starts in the Majors and a 3.05 mark in eight starts at Triple-A.

“Honestly, whatever situation that they need me, I’ll be ready for whatever opportunity that it is,” Buttó said.

The Mets chose Buttó over Tylor Megill for the role simply because Megill threw 101 pitches as a starter on Saturday and wouldn’t have been available in relief until at least Thursday. That’s why the organization optioned Megill to Syracuse after his start, knowing a fresh arm was available in Buttó.

The bullpen carousel will likely continue over the next few weeks, barring an acquisition from outside the organization. Internal options at Syracuse include Cole Sulser, Eric Orze and Josh Walker, plus rehabbing pitchers Shintaro Fujinami and Bryce Montes de Oca. But Mets officials will not be comfortable promoting Fujinami or Montes de Oca until they prove effective over multi-week stretches in the Minors.

“You’re always keeping an eye on it,” Mendoza said. “And I’ve been saying it: You’re going to need a lot. Not only the guys on the [40-man roster]. You’re going to need 50, 60 guys to get through 162-plus.”

To replace Megill in the rotation, the Mets on Wednesday will call up No. 2 prospect Christian Scott, whose month-long stay in the Minors was always meant to be temporary. Mendoza said he expects Scott to be available for a full workload when he returns to the rotation Wednesday against the Nationals.

“I’m excited for this opportunity to be back up here,” Scott said.