PITTSBURGH -- The Milwaukee Brewers slipped out of town Thursday after their lead in the National League Central continued to slip away.

The Pittsburgh Pirates' 4-2 win at PNC Park completed a four-game sweep of the Brewers that not only imperiled the first-place (for now) Brewers but thrust the home team into a tightening, four-team race.

Eight games behind on Saturday, Pittsburgh, which has won five straight and 11 of its last 13 games, now trails the Brewers by three. Milwaukee, after a fifth straight loss, leads the Chicago Cubs by one. St. Louis remained 4 1/2 games back after losing to the New York Mets.

The only team that concerns Pirates manager Clint Hurdle is his own.

"I don't think we're doing a whole lot of scoreboard watching, we're just focused on playing our best ball," he said. "We've got a game in Colorado (Friday) that we'll need to get ready for. We're really best served when we stay in the day and that's where we'll stay."

All the games were low-scoring and close, and the Pirates again got quality pitching and just enough offense. Right-hander Jameson Taillon gave up two earned runs in 5 2/3 innings, striking out eight. The bullpen was spotless, and Gregory Polanco hit his ninth home run.

Polanco's shot was one of the few hard-hit balls by the Pirates. That was one of the series' threads. Another was the Brewers' repeated failures with runners on base.

"I felt we pitched really well," Brewers manager Craig Counsell said. "Today they had some balls in good spots. We didn't play poorly, we just didn't get that next hit. They got that next hit. They dumped some balls in today. ... They make a lot of contact and they got rewarded for it."

Milwaukee, on the other hand, has contact issues. Pirates pitchers fanned 10 Brewers, who lead the majors in strikeouts.

Chris Stewart, who went 3-for-3, opened the scoring in the second inning with the Pirates' third straight two-out single.

Taillon (6-3) stranded two baserunners in the first and struck out seven in the first three innings before a walk, an infield single, Brett Phillips' RBI double and Orlando Arcia's infield out gave Milwaukee a 2-1 lead in the fourth.

Right-hander Jimmy Nelson (8-5) struck out the side in the bottom of the inning but also yielded Polanco's game-tying homer. In the fifth, RBI singles by Josh Harrison and Andrew McCutchen provided the Pirates' two-run lead.

"We're fine," Nelson said of the team's mindset. "We're still in first place."

Taillon, who underwent testicular cancer surgery on May 8 and missed nearly six weeks, gave up Manny Pina's one-out double in the sixth and departed after a season-high 116 pitches. Left-hander Matt LeBlanc and righty Juan Nicasio quelled potential rallies in relief, and lefty Felipe Rivero pitched the ninth for his ninth save.

NOTES: The Pirates start a nine-game, 10-day trip in Colorado on Friday having won five of their last six road games and nine of their last 14. ... The Brewers' five-game losing streak ties a season high set at the end of May. ... Pittsburgh has won five straight series.