PHOENIX — The lone positive during this Mets freefall has been strong starting pitching. But Friday night even Seth Lugo wandered aimlessly through the desert to get devoured by coyotes.

Lugo has been the team’s best pitcher not named Jacob deGrom. On this night he presented few if any mysteries to the Diamondbacks in the Mets’ 7-3 loss at Chase Field.

The Mets lost for the 12th time in 13 games to fall 10 games below .500. As could almost be expected, the lineup was hardly exceptional, marking the 11th straight game in which the Mets scored three runs or fewer. It tied the franchise record for such futility, set in 1981.

“The [starting pitchers] aren’t going to be perfect every night,” manager Mickey Callaway said. “On those nights the offense needs to pick you up and they didn’t.”

Callaway considered it progress that the Mets put 13 runners in scoring position. On the flip side, the Mets had only two hits in those instances.

“We’re slowly coming along,” he said. “The base runners are [accumulating] more and more the last couple of nights. The last part of it is go ahead and drive those guys in.

“We were three ground balls away from scoring five runs against their starter. I thought the intent was there, but we didn’t get the job done.”

Lugo was finished after five innings in which he allowed five earned runs on eight hits and one walk with seven strikeouts. It was by far the worst of the right-hander’s three starts this season and a rare misstep, factoring in his relief appearances.

Lugo said he didn’t feel extra pressure knowing his lineup’s struggles.

“I feel like a good clean inning will jumpstart the offense,” Lugo said. “Mix in a couple of decent innings there and we hit the ball a little bit the next half. I have to do a better job of executing pitches late in the game, the fifth inning.”

Entering play Mets starting pitchers had posted a 2.70 ERA over their past 24 games, the lowest mark in the major leagues over that stretch.

The Mets have missed Lugo’s arm in the bullpen, but until Noah Syndergaard can return from the disabled list, the Mets have no choice but to continue on this course.

“Looking at it on the surface, sure he should be in the rotation, and you really can’t argue that point,” pitching coach Dave Eiland said before the game. “But we’re a better pitching staff with him in the bullpen in my opinion, because he can impact two or three games a week rather than just one.

“Is he a solid major league starter? No question about it. But what role does he fit in that makes us the best team? That is the debate. But until Syndergaard comes back it’s a non-issue.”

Daniel Descalso launched Lugo’s 99th pitch of the night, a full-count changeup, for a two-run homer in the fifth that gave the Diamondbacks a 5-2 lead. Lugo had recorded two quick outs in the inning before David Peralta singled and Descalso hit Arizona’s fifth homer in the series.

Dominic Smith’s homer leading off the fourth against Zack Godley had sliced the Mets’ deficit to 3-2. The blast, which hit the right-field foul pole, was Smith’s first since returning from Triple-A Las Vegas earlier this week.

Lugo had a rough third inning in which he allowed three straight singles and watched Arizona score twice to take a 3-1 lead. Jake Lamb delivered an RBI single in the inning before Descalso’s sacrifice fly brought in another.

Todd Frazier’s RBI double in the third tied it 1-1, but the Mets missed a big opportunity for further damage. With runners on second and third and nobody out, Godley struck out Brandon Nimmo and Asdrubal Cabrera before Jose Bautista was caught looking at strike three on 3-2. Bautista started toward first base on the pitch and exchanged words with plate umpire Chad Fairchild.

Bautista’s troubles on the bases came in the second inning, after he reached third on Smith’s double with nobody out. First, Kevin Plawecki hit a slow grounder to third, on which Bautista retreated to the base. The inning ended with Bautista thrown out at the plate by Jarrod Dyson attempting to score on Amed Rosario’s fly to medium center.