Ike Davis’ two-run homer helped the New York Mets gain some rare momentum and a 4-1 win over the visiting Arizona Diamondbacks Friday night.

Mike Pelfrey (1-2) had far and away his most productive start, allowing one earned run on five hits with four strikeouts in seven innings. Jason Isringhausen pitched a scoreless eighth and Francisco Rodriguez recorded his third save in the ninth.

With New York trailing 1-0 in the bottom of the seventh, Davis cranked a two-out, two-run shot to center field off Esmerling Vasquez (0-1) that needed a video review.

The Mets added two more runs off Juan Gutierrez in the eighth to erase Joe Saunders’ solid start for Arizona (8-10). Saunders was charged one earned run on two hits in six-plus innings.

Davis also went deep in Thursday’s victory for New York, which won a series opener and back-to-back games for just the second time. The second-year stud has emerged as the Mets’ most reliable slugger, leading the team with 16 RBIs.