PHOENIX -- The Mets had only scored three runs in their previous 18 innings and were without their top two relievers heading into the eighth inning on Friday night. So, it may not have seemed like a comeback win was imminent.

However, New York rallied for two runs in the eighth, with pinch-hitters J.D. Davis and Carlos Gómez driving in the tying and go-ahead runs, respectively, to beat Arizona, 5-4, at Chase Field. Gomez laced an RBI double to left field that plated the winning run.

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It was a strong victory for the Mets after their seven-game National League West road trip started with three losses in four games against the Dodgers. Here were the three keys to their series-opening win over the D-backs:

1) Gomez delivers off bench
The Mets signed Gomez to a Minor League deal during Spring Training for outfield depth. Now, after the 13-year veteran opened the season with Triple-A Syracuse, he is finding ways to contribute since returning to the big leagues on May 17.

Gomez went 1-for-13 in his first six games with New York. However, he now has a hit in three of his last four games, including Tuesday’s win over the Dodgers when he went 3-for-5 with a double.

“Gomie has put great at-bat after great at-bat together,” Mets manager Mickey Callaway said. “Credit to us going out and getting the depth pieces that we need in case something like [an injury] happens and we need to weather the storm.”

Gomez’s go-ahead two-bagger completed the rally in the eighth. Todd Frazier, Adeiny Hechavarria and Davis hit three consecutive two-out singles -- with Davis’ driving in the tying run -- before Gomez hit a ball just fair down the left-field line.

“This is what good teams do,” Gomez said. “Whether you start the game or not, you have to be ready for some situation like that.”

It’s possible another run could have scored on the play, but the ball retriever picked up the live ball, making it a ground-rule double and forcing Davis to stay at third. However, the Mets’ bullpen made the one-run lead stand.

2) Lugo’s return
Callaway said he wasn’t going to shy away from using reliever Seth Lugo in high-leverage situations, even though the right-hander hadn’t pitched since May 20 due to right shoulder tendinitis. Lugo didn’t go on a rehab assignment and was activated from the injured list prior to Friday’s game.

Sure enough, the Mets’ manager turned to Lugo looking for a shutdown inning to protect the one-run lead in the eighth.

Although Lugo gave up a one-out triple to Eduardo Escobar, he got Adam Jones to pop out to second base and -- after an intentional walk to Christian Walker -- got Tim Locastro to pop out to shortstop.

It was an encouraging sign that the Mets can depend on Lugo to pitch key innings moving forward. And it was crucial in this game, as top relievers Edwin Díaz, Jeurys Familia and Robert Gsellman had carried a heavy workload this week.

“It just makes it easier for us to get wins,” Callaway said of Lugo’s return. “He’s a guy we’re going to count on.”

3) Gsellman fills in for the save
Diaz and Familia had each pitched four times in a six-day span. That’s why Callaway didn’t use either right-hander on Thursday, and he again opted not to use either Friday.

“The more and more we looked at it, after they played catch, they said they were OK, [pitching coach] Dave [Eiland] and I talked about it, Diaz and Familia were down,” Callaway said. “They’ve thrown a ton of pitches, and we just couldn’t do it. I think taking care of our players and putting them in a good spot is always something we’re going to think about.”

The Mets still secured a win. Gsellman pitched around a one-out walk in the ninth to notch his first save of the season and complete New York’s comeback victory.

“I’ve always had the mentality that every time I take the mound it’s the same, whether it’s the first or the ninth,” Gsellman said. “So, I just go with that, and it’s been working.”