PITTSBURGH (AP) Gregory Polanco saw one of the fastest players in baseball standing at third and knew there was little margin for error.
A month ago, the Pittsburgh Pirates outfielder might not have had a shot at throwing out Colorado's Jose Reyes. Now things are different. The talented, but still raw, right fielder is maturing nearly as quickly as his surging team is racking up victories.
Polanco's throw easily beat Reyes to the plate to preserve a tie in the eighth and he added an insurance run after Josh Harrison put the Pirates in front in the bottom of the inning as Pittsburgh escaped with a 5-3 victory Friday night.
''He's refining his routine through his practice, and he is nailing it in games,'' Pirates manager Clint Hurdle said. ''In high-leverage situations he is nailing them.''
The 23-year-old finished with three hits, an RBI that provided the final margin and two outfield assists. The first caught Nick Hundley in a rundown between first and second in the fifth. The second was a low laser that gave catcher Francisco Cervelli plenty of time to tag Reyes as the four-time All-Star tried to slide by.
''I just tried to put a good throw, throw it in the right direction, that's the first thing,'' Polanco said. ''You try to throw it anywhere else, you've got no chance.''
The momentum helped carry the Pirates to their 13th win in their last 16 games as they try to keep pace with St. Louis in the hyper competitive NL Central. Harrison came on as a pinch-hitter and lined a single off Scott Oberg (3-3) to score Cervelli and put Pittsburgh in front, the first run given up by the Colorado bullpen in 18 2-3 innings.
Polanco followed with a single as Pittsburgh improved to 20-4 against the NL West, though his arm is becoming as effective as his bat at times.
''I'm sure the scouting report says something,'' Harrison said. ''They keep testing him. But if they keep testing him they'll get the same result and I'm cool with it.''
Tony Watson (3-1) earned the win thanks to Polanco's throw. Mark Melancon worked a perfect ninth for his major league-leading 42nd save. Pittsburgh relievers have won 18 straight decisions since last taking a loss on June 25.
Reyes hit his third home run of the season for Colorado and manager Walt Weiss had no problem with Reyes' decision to dart for home on the shallow fly ball by Nolan Arenado.
''I was glad he took off, it took a great throw by Polanco,'' Weiss said. ''It was right on the money and it wasn't real deep but I thought certainly deep enough for Reyes to take a shot.''
Carlos Gonzalez added his 31st homer but the Rockies dropped their sixth straight game to the Pirates at PNC Park.
Colorado rookie starter Jon Gray improved over his miserable start against the New York Mets last week, when the former first-round draft pick gave up seven runs without getting out of the second inning.
While he was hardly crisp - he went over his initial 75-pitch allotment by throwing 89 before leaving with one out in the fifth - he avoided major trouble by striking out Neal Walker with the bases loaded to end the third.
''I was OK with it,'' Gray said. ''It was a lot of stuff I can't control but I think I was battling pretty well.''
Pittsburgh improved to 11-0 in Francisco Liriano's last 11 starts since being on the other end of Washington's Max Scherzer's no-hitter on June 20, the second-longest unbeaten stretch by a Pittsburgh starter in 42 years. He had no major worries until Reyes' two-run shot off the foul pole in the fifth and a long solo homer to center by Gonzalez in the sixth and leaving with a no-decision.
Rockies: 1B Justin Morneau was scheduled to play five innings Friday night for Double-A New Britain as he continues his slow return from concussion-like symptoms and a cervical neck strain. The 34-year-old four-time All-Star hasn't appeared in a Colorado uniform since going on the DL in May. ... Colorado called up LHP Jason Gurka and sent RHP Tommy Kahnle to Triple-A Albuquerque.
Pirates: RHP A.J. Burnett is scheduled to throw three innings off the mound Sunday as he continues his comeback from a flexor strain in his right elbow. Burnett worked some curveballs into the mix during a session in Miami on Thursday but Hurdle said it's too early to tell when the 38-year-old will be available.
Pittsburgh's J.A. Happ will make his fifth start for the Pirates since coming over at the trade deadline from Seattle. The 31-year-old is 2-1 with a 2.08 ERA with Pittsburgh and is 1-0 with a 1.89 ERA in four career appearances against Colorado. Rockies starter Chris Rusin is coming off the worst performance of his career, giving up 11 runs and 12 hits in a loss to the New York Mets on Aug. 22.
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