Alex Rodriguez had a season-high four hits and the Yankees erupted for eight runs in the seventh inning to claim the first leg of the Subway Series and beat the Mets 9-3 Sunday afternoon.

Derek Jeter’s two-run single with the bases loaded off Mike Pelfrey tied the game at 3-3 in the seventh, but that was just the beginning of the monstrous frame. Pelfrey was pulled and the Mets’ next three relievers each gave up runs, including Pedro Beato, who allowed his first run of the season when Rodriguez slapped an infield single to put the Yankees up 4-3.

Pelfrey (3-4) was charged with five earned runs on eight hits and struck out four in six-plus innings.

Yankees starter Ivan Nova was knocked around for 11 hits but surrendered just three earned runs and one walk in 6 2/3 innings. Luis Ayala (1-0) and Lance Pendleton filled in from the Yankees’ bullpen.

Willie Harris had three hits for the Mets, who scored all three of their runs in the second. They have scored three runs or less in six straight games.