PITTSBURGH -- The Pittsburgh Pirates didn't get embarrassed against Max Scherzer this time.

Right fielder Gregory Polanco had two hits, including a home run, and drove in three runs while first baseman Pedro Alvarez and second baseman Neil Walker also homered to lead the Pirates to a 7-5 victory over the Washington Nationals on Friday night.

Scherzer, the Nationals ace right-hander, pitched a no-hitter the last time he faced the Pirates on June 20 at Washington, but was not nearly as sharp this time while not factoring in the decision.

Scherzer was tagged for all three home runs while giving up five runs and seven hits in five innings with one walk and eight strikeouts.

"I felt good. Just made some mistakes," Scherzer said. "They made me pay for it. They know what I've got and sometimes that's just the way baseball goes. It takes a little bit of luck to throw a no-hitter. They hit some balls hard last time. They just went at people."

Walker, rookie third baseman Jung Ho Kang and catcher Francisco Cervelli also had two hits each for the Pirates, who had a total of 12.

Kang extended his hitting streak to a career-high 11 games. Walker hit the second of back-to-back homers with Polanco in the fifth inning to put the Pirates in front 5-4.

Scherzer, who was signed to a seven-year, $210-million contact as a free agent in the offseason, remained 10-8 and is 1-3 in his last five starts. He is also 0-2 in four career starts at PNC Park.

"We haven't seen that this year," Nationals manager Matt Williams said of Scherzer getting hit hard. "It's going to happen. He'll be ready for his next one."

The Pirates (56-40) scored twice in the bottom of the sixth inning off rookie left-hander Sammy Solis (1-1) to break a 5-5 tie as pinch hitter Brent Morel stroked an RBI double with two outs and scored on Polanco's single.

"It feels good to get a big pinch hit," Morel said. "The guys are out there playing hard and you want to do your part to help win the game when you get your chance."

Pirates closer Mark Melancon worked around two singles to pitch a scoreless ninth inning for his 31st save in 32 opportunities.

The Pirates won the first two games of the four-game series following a 1-5 road trip to Milwaukee and Kansas City coming out of last week's All-Star Game. Pittsburgh increased its lead to 4 1/2 games in the National League wild card but remained six games behind the St. Louis Cardinals in the NL Central.

The first-place Nationals (51-44) stayed three games ahead of the New York Mets in the NL East.

Right-handed reliever Vance Worley (4-5) got the win despite allowing shortstop Ian Desmond's leadoff home run in the top of the sixth that drew the Nationals even. It was Desmond's second homer in as many games and 10th of the season.

Pirates starter Jeff Locke pitched five innings and did not factor in the decision as the left-hander allowed four runs and four hits while walking three and striking out five.

Polanco hit his fourth home run of the season, a two-run blast to cap a 12-pitch plate appearance after pinch hitter Jaff Decker drew a leadoff walk. Walker followed with his eighth homer.

"I was just trying to foul off good pitches and keep battling until I got a pitch I liked," said the 23-year-old Polanco, who is in his first full major league season. "I've had 10-pitch, 11-pitch at-bats in the minor leagues and last year but that was my best at-bat this year."

Pirates manager Clint Hurdle loved how Polanco hung tough against Scherzer.

"He really put his nose into that at-bat," Hurdle said.

The Nationals batted around in a four-run fourth to take a 4-2 lead. Catcher Wilson Ramos and second baseman Dan Uggla sandwich RBI singles around first baseman Tyler Moore's two-run double.

Alvarez opened the scoring with a two-run home run in the second, a 460-foot shot that cleared the stands in right-center field and bounced in to the Allegheny River on one hop. It was Alvarez's 14th homer of the season and the second in as many games.

NOTES: Washington 1B Clint Robinson was scratched moments before game time because of illness but entered the game at the start of the sixth inning. ... Nationals 3B Yunel Escobar (sore left wrist) missed a second straight game and remains day-to-day. ... Pittsburgh 1B/OF Corey Hart (left shoulder impingement/right knee discomfort), who has been on the disabled list since June 22, went home to Litchfield Park, Ariz., on Friday and will continue his rehab there.