NEW YORK (AP) Aramis Ramirez had four hits and three RBIs, Pedro Alvarez homered and Pittsburgh roughed up the sloppy Mets after a rain delay Sunday for an 8-1 victory that sealed the Pirates' first season series sweep of New York.

Alvarez, Ramirez and Gregory Polanco each had run-scoring hits in a breakaway four-run seventh, keyed by reliever Bobby Parnell's throwing error. The Pirates beat the NL East leaders in extra innings the previous two nights.

Pittsburgh also scored on a passed ball by Travis d'Arnaud in their sixth straight win over this potential postseason foe. The Pirates swept the Mets at home in a three-game set in May.

More from FoxSports

Alvarez homered off Matt Harvey in the second, and d'Arnaud connected off Jeff Locke in the bottom half. Harvey and Locke matched each other in a gritty duel until a sudden sun shower turned to a heavy storm in the bottom of the sixth.

Booming thunder and crackling lightning got a scream from the crowd of 40,250 - and a jump and a dash from Daniel Murphy, who had just walked. The Mets second baseman was startled by the clap and flash and ran from the field before umpires even called for the tarp.

After the 42-minute delay, Arquimedes Caminero (4-1) got two crisp outs with runners on first and second to end the inning.

The Mets then lost their footing.

Parnell (1-3), who got the defeat in the opener of the series Friday, was booed as he yielded four runs - two earned - in relief of Harvey.

In two outings this series, Parnell gave up five hits and six runs - four earned - while only getting two outs. He was booed off the mound after both appearances.

Parnell's throwing error to second base in the seventh helped Pittsburgh score four times.

Pirates relievers got the win in all three games, tossing 15 innings. They gave up one run, six hits and two walks while striking out 17.

Ramirez had a two-run double in the eighth for Pittsburgh, which completed its major league-best 13th sweep this season - their most sweeps since 1991.

Harvey gave up seven hits and a run in six innings. He walked one, ended a three-start streak without offering a free pass.

Locke had allowed at least three runs in each of his previous six starts, yet he was just as resolute as Harvey. He gave up four hits and walked two - one intentional.

TRAINER'S ROOM

Pirates: Andrew McCutchen, Francisco Cervelli and Jung Ho Kang were all out of the starting lineup, a day after playing 14 innings. ''When the guys gets tired they're tired. When you need to get them out, you need to get them out,'' manager Clint Hurdle said of resting the three starters at same time. ... RHP Vance Worley threw 75 pitches for Triple-A Indianapolis on Saturday night, his first action since being designated for assignment July 30 and accepting a demotion to the minors after clearing waivers.

Mets: 1B Lucas Duda (lumbar strain) did not start for a fifth straight game. He walked as a pinch hitter in the 12th Saturday and should be back in the lineup Tuesday, after an off day.

UP NEXT

Pirates: Gerrit Cole tries for a majors-leading 15th win when Pittsburgh opens a seven-game homestand against Arizona. The right-hander has lost his last two outings but is 2-0 with a 1.98 ERA against Arizona in two career starts.

Mets: Jacob deGrom is on a 15-start roll, with a big league-best 1.46 ERA in that span. He makes his sixth career start against an AL team (2-2, 3.06), when New York faces the Orioles in Baltimore on Tuesday.