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Clint Hurdle insists the Pittsburgh Pirates don't hype up for big games. The manager has preached a steady approach from the moment he took over nearly five years ago. April or September, it doesn't matter.

"It's not like we have a big-series button when it's shared with us that it's a big series," Hurdle said.

Maybe, but his streaking team certainly seems to play like it.

Pedro Florimon scored on Starling Marte's sacrifice fly in the eighth inning, and the Pirates beat the Chicago Cubs 5-4 in the first game of a day-night doubleheader Tuesday to inch closer to first-place St. Louis in the NL Central.

Tied 4-4, Florimon entered as a pinch runner after Pedro Alvarez worked a leadoff walk against Justin Grimm (3-5). Florimon stole second and sprinted to third when the throw from catcher Miguel Montero rolled into center field.

Marte, playing for the first time since injuring his shoulder last Thursday, hit a sharp liner to left. Florimon flew Superman-style across home plate to easily beat Austin Jackson's throw as the Pirates momentarily moved five games ahead of the Cubs for the top NL wild-card spot and within two of the Cardinals.

Tony Watson (4-1) pitched a scoreless eighth. Mark Melancon worked a perfect ninth for his major league-leading 46th save, tying the club record Mike Williams set in 2002.

"Great victory! I'm honored to be a part of such a rich history here in (hash)Pittsburgh (hash)46," Melancon tweeted after Pittsburgh won its fourth straight.

Travis Snider drove in two runs for the Pirates. Andrew McCutchen had two hits, and Neil Walker provided an RBI double as Pittsburgh improved to 32-15 in one-run games, including 21-5 at PNC Park.

Montero had two hits for the Cubs, who took advantage of two wild pitches from Joakim Soria to rally from a 4-1 deficit.

"There were a lot of gifted runs in that game," Cubs manager Joe Maddon said. "We gave them runs and they gave us runs, too, but we've got to do a better job, especially in a close game."

Pittsburgh starter Gerrit Cole gave up four runs (three earned) in 6 1/3 innings in his return after the Pirates skipped his last turn in hopes of giving their 25-year-old ace a breather before the stretch run. Cole struck out eight without issuing a walk and settled down after surrendering an unearned run in the first. He retired 11 straight at one point before the Cubs took advantage of a couple breaks to get back in it in the seventh.

"I had some good weapons today," Cole said. "I thought the stuff was pretty crisp."

Montero singled off first baseman Alvarez's glove with one out, and Starlin Castro followed with a grounder that kicked off Cole's leg. Pinch hitter Tommy La Stella doubled home Montero, and the Cubs tied it without needing a hit thanks to the wild pitches by Soria, who now has five wild pitches in 21 appearances with the Pirates after not throwing one in 46 games with Detroit.

The mistakes bailed out Chicago starter Jason Hammel, who didn't make it out of the fourth inning for the fourth time since July 8. He allowed four runs in 3 2/3 innings. Snider hit a two-run single in the first, and Walker added a two-run double in the fourth that sent Hammel off in favor of reliever Trevor Cahill.

"What I'm doing right now isn't acceptable," Hammel said. "I've got to get to work because we're running out of time.

YOU'RE OUT

Pittsburgh collected its major league-leading 32nd outfield assist in the fifth when right fielder Gregory Polanco threw out Cahill at first on a sharp liner. The play wasn't even that close, with Polanco's throw beating Cahill -- making just his seventh plate appearance of the season -- by at least two steps.

"I let Pedro (Alvarez) know before it happened," Polanco said. "...I tell him I'm playing shallow if he hits it over here, I'm going to throw it. I know he's not fast."

Marte leads the Pirates with 12 outfield assists, followed by Polanco (10) and McCutchen (7).

UP NEXT

Cubs: LHP Jon Lester (9-10, 3.50) goes for just his second win in his past six starts in the second game. Lester is 1-1 with a 2.08 ERA in two career starts against Pittsburgh, including seven strong innings in a victory on May 16.

Pirates: LHP J.A. Happ will take a five-game winning streak into the second game. Happ is 5-1 with a 1.79 ERA in seven starts for Pittsburgh since being acquired from Seattle at the trade deadline.