ATLANTA — Noah Syndergaard landed on the 10-day disabled list Monday with a partially torn lat muscle in his right side, leaving the Mets to face a new round of scrutiny about how they handle injuries.

General manager Sandy Alderson said the team’s top pitcher will be out a “considerable amount of time,” a period that he believes will be “measured in weeks” rather than days, as the Mets attempt to revive their season.

Syndergaard posted a lengthy message on Twitter late last night. An excerpt: “Today was extremely tough. Even harder than I thought when I turned the game on . . . I HATE not competing and being with my teammates . . . ”

The loss of Syndergaard comes against the backdrop of a familiar malady for this franchise — intrigue about whether the injury could have been prevented. In this case, it centers on Syndergaard’s refusal to have an MRI on an arm that he believed required no such exam, and the team’s willingness to go along with a self-diagnosis that proved too rosy.

Alderson said it ultimately was his decision, based on “input from a variety of different sources, including from Noah himself.” From those conversations, Alderson believed Syndergaard was physically ready to pitch.

“The MRI was not dismissed out of hand simply because Noah said he wouldn’t do it,” Alderson said. “We had to evaluate whether it was important to do so in spite of his opposition. That was factored into the decision as well.”

advertisement | advertise on newsday

Syndergaard’s injury and Yoenis Cespedes’ recent arrival on the DL have revived criticism about the Mets’ medical staff. Those issues predate Alderson’s arrival as GM, and he acknowledged that the recent outbreak added to the perception that he hasn’t improved that situation. But he also called the criticism disproportionate to the consequences and questioned what his motive would be for downplaying injuries.

“When I came to the Mets, that was one of the criticisms: that we had injuries, we didn’t explain injuries, we were too optimistic about when players would come back,” Alderson said. “And here we are seven years later and the same accusations are being made. I think it’s a little overblown, yeah.”

The GM also defended the club’s medical staff and insisted that he has “absolute confidence” in the information relayed to him by team doctors.

When asked if he regrets anything in his decision process regarding Syndergaard, Alderson did not provide an example. “That’s a hard question,” he said. “But let’s assume that he got the MRI and it didn’t show anything and he got injured. Am I better off? Well, the team’s not better off. Am I better off personally because it looks like I’ve covered my [expletive]? Does that really change the outcome?”

Alderson did not mention the possibility that an MRI would have revealed a lat injury. It was a reflection of the club’s belief that Syndergaard’s lat issue is not tied to the biceps tendinitis he initially felt, though a doctor told Newsday’s David Lennon that a connection between the two injuries is possible.

Mets videos

Said Alderson: “It’s not to say that things couldn’t have been done differently, but from my standpoint, I made the decision, and as I said, based on the most recent medical opinion that I’ve gotten, there wasn’t any connection between the injury and the purported discomfort in his biceps.”

He said it was impossible to know if Syndergaard’s workouts to add muscle during the offseason were a factor or if the injury was a product of overcompensating on Sunday. Some in the organization have wondered if Syndergaard injured himself while throwing 100 mph in the first inning Sunday in an effort to prove he was healthy.

Regardless of any connection, the Mets must face the reality of having to pull out of their rough start without one of the best pitchers in baseball.

Reliever Paul Sewald was summoned from Triple-A Las Vegas on Monday to give the Mets a fresh bullpen arm. They are expected to promote Rafael Montero in time to start Friday, which would have been Syndergaard’s next scheduled outing.

Alderson did not rule out signing veteran depth for the rotation.

advertisement | advertise on newsday

“This would probably accelerate that process,” he said. “But I think we have to be realistic about what may be out there.”