NEW YORK -- Jacob deGrom’s progression from a stress reaction in his right scapula has been slow but consistent. deGrom’s latest set of imaging tests on Monday came back “pretty clean” and “looked really good,” according to Mets general manager Billy Eppler, but that update came with a caveat: deGrom still hasn’t been cleared to throw off a mound, and it’s unclear if he will require more tests before receiving such permission.

For now, deGrom remains at least a month away from a return, which represents a best-case scenario; his timeline may wind up becoming more elongated and could easily leak into July, or even the second half of the season. Once he does begin ramping up, deGrom will require three to five Minor League rehab starts in his progression back from a stress reaction in his right scapula, according to pitching coach Jeremy Hefner -- a process that will take weeks to complete.

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“When you start talking about bone, it’s a little different than muscle tendons,” Hefner said on Monday. “You don’t want to mess around with bone, especially with a stress reaction in bones. We don’t want to mess around with reinjuring that type of situation, because then he’s done for the year. So we’re definitely going to play the long game with him to make sure that we have him for the rest of the season.”

As of this week, deGrom was throwing off flat ground up to 75 feet in Florida. He will continue to build up distance and velocity in his throwing program until it’s time to climb atop a mound, at which point deGrom will go through a series of bullpen sessions before appearing in Minor League games. Only once he stretches out over the course of weeks in the Minors will deGrom be ready for a return.

Monday’s MRI and CT scan were deGrom’s third set of images since he initially complained of shoulder pain in late March.

“Obviously, we want him back as soon as possible,” Hefner said. “But you’ve got to really make sure that he’s built up properly, and everyone feels good, he feels good. … We need to make sure that not only are we doing what’s best for the Mets, trying to win the World Series this year, but also what’s best for the player.”

“One of the things that we’ve tried to be consistent with here,” added Eppler, “is just not setting timelines on people.”

deGrom, who has missed time the past three seasons due to shoulder, elbow, forearm, lat and back pain, can become a free agent after the season. He has said that he intends to trigger that opt-out in his contract regardless of his injury status.

Once deGrom begins throwing in earnest, Mets manager Buck Showalter expects the two-time Cy Young Award winner to rejoin the team in New York. Right now, he and Hefner have been communicating with their ace through phone calls and text messages, with the Mets’ performance staff handling the bulk of the interaction.

“You can tell he’s really looking forward to getting back,” Showalter said. “It was a curve that was thrown to us early, and we are just going forward with it. It’s just something we had to deal with. It’s exciting to think that he’s making progress to being back with us, but we don’t assume anything.”

deGrom, Hefner added, is in fine spirits, “throwing without pain or issue or anything like that.” He’s been watching from afar as the Mets have handled his absence with aplomb, sprinting out to one of the best records in the National League. Earlier this week, deGrom FaceTimed with several members of the team, doing his best to remain involved. One of his longtime teammates, Brandon Nimmo, laughed that deGrom often texts him about random, non-baseball things, such as pictures of coyotes he sees on his property.

“He’s doing extremely well,” Hefner said. “He’s doing everything he should be doing right now, so all signs are pointing positive.”