PITTSBURGH -- The Pittsburgh Pirates allowed a three-run lead to slip away against Chicago Cubs right-hander Jake Arrieta. That would have signaled a Cubs victory a few weeks ago.

Quite a bit has changed in those weeks, though. The Pirates chased Arrieta in the seventh inning, scored four runs and took a three-run lead they would extend to four and carry to an 8-4 win against the Cubs at PNC Park on Friday.

"We battled. I thought we battled very well," Pirates manager Clint Hurdle said. "We just kept playing. We stayed in the hunt."

Chicago trailed 3-0 following a troubling second inning for Arrieta, which started with a lead-off home run from third baseman David Freese, but came back to take a 4-3 lead with three runs coming off home runs by Anthony Rizzo and Miguel Montero in the sixth and seventh innings, respectively.

That lead didn't last.

Arrieta, who faced Pirates left-hander Francisco Liriano, left the game after allowing three straight hits to start the seventh inning, punctuated by a John Jaso single that scored Adam Frazier from third base to tie the game 4-4.

The Pirates took a 5-4 lead when Rizzo tossed Gregory Polanco's dribbler behind left-handed pitcher Travis Wood, allowing Josh Bell to score in his MLB debut. Andrew McCutchen then added a sixth run with his third hit of the game, a single to center field.

"The thing about (Arrieta) is he gives you opportunities," McCutchen said. "We've had plenty of opportunities. There have been maybe a handful of times when he's faced him and he's been lights-out. But a lot of times in a lot of games where we face him, we've had a lot of opportunities. Today was just, we were able to come through in those opportunities that we got more times than not."

Starling Marte grounded out to second base, but the Cubs weren't able to turn a double play, a following Eric Fryer to score and push the Pirates' lead to three runs.

Matt Joyce scored on a wild pitch in the bottom of the eighth inning to put Pittsburgh ahead 8-4.

The Pirates (45-42) have won eight of their past nine games to pull within 7.5 games of the National League Central-leading Cubs (52-34), who have lost four straight.

After going down in order in the first inning, the Pirates scored three runs on two homers in the second.

Freese led off the inning with his 10th home run of the season on a 1-0 pitch, going to the opposite field just over the right-field wall and inside the foul pole. The home run was Pittsburgh's first off Arrieta since Sept. 13, 2013, when Garrett Jones hit Pittsburgh's last of three home runs in four pitches.

Marte followed Freese's home run with a single to left field through shortstop Addison Russell. Marte stole second base before advancing to third on Josh Harrison's flyout to center field.

Shortstop Sean Rodriguez took Arrieta deep to left field for his eighth home run of the season. Arrieta cleaned up the inning with back-to-back strikeouts of catcher Erik Kratz and Liriano but trailed 3-0.

Cubs manager Joe Maddon attempted to explain Arrieta's recent struggles.

"The best way to describe is it's just command," Maddon said. "Last year, we just saw him keep nailing his pitches all the time and it's hard to do what he did so consistently, especially throwing as many breaking ball strikes as he did."

Friday marked the first time that Arrieta surrendered at least one home run in three consecutive starts since July 2011, when he allowed a home run in five straight starts with the Baltimore Orioles.

The three earned runs allowed in the second equaled the combined total of the earned runs Arrieta allowed in his previous six starts against Pittsburgh.

Arrieta, who allowed six earned runs Friday, has surrendered at least four earned runs in each of his past three starts and has lost in three of his past four starts after starting the season 11-1. He had not allowed more than two runs in any of his previous three starts against the Pirates this season.

"I felt good tonight. I had a good feel for some things," Arrieta said. "I had a good direction to the plate. ... There's some positives there but giving six runs, especially the ones in the seventh, is my takeaway."

The Cubs got one run back in the top of the fourth when center fielder Jason Heyward tripled off the center-field wall before scoring on third baseman Javier Baez's groundout to cut the Pirates' lead to 3-1.

NOTES: The Cubs didn't arrive in Pittsburgh until early Friday morning after losing 4-3 in 11 innings to the Braves after the start of the game on Thursday was delayed by rain. ... Chicago moved OF Kris Bryant from right field to left on Friday. Ben Zobrist, who started in right field on Thursday, moved to second base and hit leadoff. INF Javier Baez replaced Tommy La Stella at third base. Baez played second base on Thursday. C Miguel Montero replaced Willson Contreras behind the plate. Contreras played left field. ... The Pirates promoted 1B Josh Bell from Triple-A Indianapolis and optioned RHP Tyler Glasnow a day after he made his major league debut. Pittsburgh manager Clint Hurdle said Bell, the Pirates' third-best prospect according to Baseball America, would be used as a bat off of the bench in the weekend series. He pinch-hit in the pitcher's spot in the order in the seventh inning and laced a single to center field. ... LF Starling Marte re-entered Pittsburgh's lineup after taking a day off during its 5-1 loss to the Cardinals on Thursday.