LOS ANGELES — Jacob deGrom struck out 13 over seven scoreless innings in his postseason debut and Daniel Murphy homered off a star-crossed Clayton Kershaw to help the New York Mets defeat the Los Angeles Dodgers 3-1 on Friday night for a 1-0 lead in their NL Division Series. DeGrom limited the Dodgers to five hits and walked one. The right-hander’s strikeouts tied the franchise playoff record set by Tom Seaver in Game 1 of the 1973 NL Championship Series. Kershaw endured his fifth straight postseason loss after giving up the seventh playoff homer of his career. Last season’s NL MVP allowed three runs and four hits in 62/3 innings, struck out 11 and walked four. Three of Kershaw’s walks came in the seventh, before Mets captain David Wright had a two-out, two-run single off Pedro Baez that put New York up 3-0. Greinke (19-3, major league-best 1.66 ERA) beat the Mets 4-3 on July 4 at home in his only start against them this season. Syndergaard (9-7, 3.24) had a no-decision in the Mets’ 2-1 win at Dodger Stadium on July 3 in his only career start against Los Angeles. Kershaw, the major-league strikeout leader with 301 in the regular season, retired six of his first nine batters. DeGrom, last year’s NL rookie of the year, struck out two batters in each of his first four innings. DeGrom became the first Mets pitcher with 10 or more strikeouts in the playoffs since Dwight Gooden in Game 1 of the 1988 NLCS at Dodger Stadium. “To have him go out there against Clayton tonight and win the game is a huge lift for us,” said Mets manager Terry Collins, who got a victory in his postseason debut at age 66. The Dodgers finally scored in the eighth on Adrian Gonzalez’s two-out RBI single that left them trailing 3-1. With two runners on, he hit a long fly ball to center field that was caught by Yoenis Cespedes to end the inning. The Dodgers lost the final two games, with Kershaw tagged for the loss pitching on three days’ rest in Game 4.