Edwin Diaz’s trapezius discomfort wasn’t severe enough Sunday to warrant a move to the injured list.

The Mets reliever was unavailable to pitch in Sunday’s 2-1 loss to the Braves, a day after he was removed from the game with upper-back soreness, but manager Mickey Callaway indicated Diaz was “slightly improved.”

On Saturday, the right-hander allowed a homer to Freddie Freeman in the ninth inning before walking another batter. He was charged with two earned runs over one-third of an inning, boosting his ERA to 5.55 in his nightmarish season.

Amed Rosario started in the leadoff spot over Jeff McNeil largely because left-hander Dallas Keuchel started for the Braves, according to Callaway. But the manager also wanted to capitalize on Rosario’s hot bat. McNeil was starting for the first time since returning from the injured list a day earlier.

“I do love the way Rosie has performed in that leadoff hole, we all know he has a lot of success there,” Callaway said. “McNeil behind him, if [Rosario] gets on first the hole is open for McNeil to hit a ground ball through the right side. If he gets on second, I feel McNeil can pull the ball and move the runner over, so there is a few reasons we like McNeil in that two-hole.”

Rosario went 1-for-4 in the Mets’ 2-1 loss to the Braves at Citi Field. McNeil was hitless in three at-bats.

Callaway indicated Marcus Stroman is “very likely” to start Tuesday versus the Cubs. The righty departed from his last start with left hamstring tightness. Stroman is 1-0 with a 4.57 ERA in his four starts for the Mets.

Brandon Nimmo played nine innings in center field and went 3-for-4 with two doubles and two RBIs in a minor league rehab appearance for Triple-A Syracuse.

J.D. Davis finished 2-for-3 and is hitting .359 with a 1.084 OPS at Citi Field this season.

Justin Wilson pitched a scoreless ninth inning with two strikeouts and owns a 0.95 ERA in 23 appearances since returning from the injured list on July 2.

The Mets’ ninth-inning rally ended a scoreless streak by the Braves bullpen that had extended to 25 innings. The streak was the Braves’ longest since at least 1974, according to the team.