Washington Nationals right fielder Bryce Harper is tagged out by Pirates shortstop Jung Ho Kang during the first inning Sunday at PNC Park. Harper was trying to stretch a single into a double. The Pirates picked up a 3-1 win, taking three of the four games in the series.

PITTSBURGH — Gregory Polanco got Gerrit Cole on track, and the ace right-hander took over from there.

Cole became the majors' first 14-game winner, leading the Pittsburgh Pirates to a 3-1 victory over the Washington Nationals on Sunday.

Cole (14-4) allowed one run and seven hits in 7 2/3 innings while improving to 3-1 with a 2.40 ERA in four July starts. The right-hander struck out eight and walked none.

He also became the first Pittsburgh pitcher with 14 wins before August since Dock Ellis in 1971.

“It's been a collective effort to get the wins where they are,” Cole said.

Cole got a big assist from Polanco in the first after he left a pitch up to Bryce Harper and the All-Star lined it to the wall in right. Polanco fielded the ball as it caromed off the wall, and then sent a laser to second base that beat Harper and ended the inning.

“He did an excellent job of cleaning up that mistake and it just kind of set the tone,” Cole said. “We were going to play crisp defense, we were going to come at you and it was a nice way to start the game off.”

Danny Espinosa chased Cole with a single that put two runners on for Harper, who grounded out against left-hander Tony Watson. Mark Melancon picked up his major league-best 32nd save with a scoreless ninth.

“We had the opportunity but it just didn't work out,” Nationals manager Matt Williams said.

Michael Taylor put Washington in front with a two-out homer in the third, but Pittsburgh responded with two runs in the bottom half. Polanco and Andrew McCutchen each had an RBI single against Joe Ross (2-3).

Neil Walker led off the fourth with his ninth home run, extending Pittsburgh's lead to 3-1.

Ross retired nine in a row before Matt Thornton relieved him in the seventh. He struck out seven and allowed five hits.

“I felt pretty good,” Ross said. “The guys behind me played great. They put the ball in play off me and our guys made the plays behind me.”

Pittsburgh set a PNC Park four-date attendance record by drawing 151,952 fans during the series against NL East-leading Washington.One of a kindWhen Watson faced Harper in the eighth, the slugger grounded a 1-2 pitch sharply to the right side between Walker and first baseman Sean Rodriguez.Rodriguez stepped to his right and flashed his glove up high as the ball took a sharp hop. He then tossed to Watson covering first for the out.“The last play might be a play only Rodriguez can make,” Pirates manager Clint Hurdle said. “To lay out, the wicked hop at the end, stay with it, and Watson's so athletic you know he's going to be there.”Trainer's RoomPirates: 3B Josh Harrison played catch and took ground balls. Harrison was placed on the 15-day disabled list July 6 after he tore a ligament in his left thumb.

Pirates second baseman Neil Walker is congratulated by teammates after leading off the fourth inning with a solo home run Sunday at PNC Park. The Pirates picked up a 3-1 win over the Washington Nationals.