Steven Matz still missing a playoff necessity, but Mets roll

Steven Matz Photo: APATLANTA — Steven Matz still has a leap to make before the Mets can consider him as part of a potential playoff rotation.

The rookie lefty was effective enough to pick up a win Friday night, but his key number is seven — as in pitching into the seventh inning — and Matz isn’t there yet.

With a major assist from the bullpen and Yoenis Cespedes’ bat, the Mets beat the Braves 5-1 at Turner Field on a night Matz never found a rhythm.

Cespedes iced it with a monstrous two-run homer in the ninth, as the Mets — who won their fifth straight — moved 8 ½ games ahead of the Nationals in the NL East. The Nationals lost 2-1 at Miami in their first action since the Mets swept them three…