(SportsNetwork.com) - Aaron Harang will try to extend the Philadelphia Phillies' longest winning streak since 2012 on Tuesday evening in the second of four straight matchups with the Colorado Rockies.

Even with a current string of six straight victories, the Phillies remain six games under .500 at 17-23, but Harang has been a key offseason addition. He is 4-3 with a 2.03 earned run average through his first eight starts.

Harang is coming off another gem as he logged eight scoreless innings of five- hit ball to beat the Pittsburgh Pirates 4-2 on Thursday. The righty walked one batter and struck out six for his third scoreless outing of the campaign. It also marked the sixth time this season he has yielded two or fewer earned runs.

"I'm having fun," Harang said. "I know what I can do and I know my limitations. And I know that I have to control myself and get through tough situations and trying to stay positive."

The veteran hurler is an even 6-6 in 14 career starts against the Rockies with a 4.50 ERA.

The Phillies kept up their winning ways with last night's 4-3 victory, keyed by Odubel Herrera's two-run double in the sixth inning. Ben Revere added a three-hit game, while Ryan Howard and Carlos Ruiz each plated a run to extend Philadelphia's longest winning streak of the season.

Cole Hamels surrendered just one run on six hits and a walk with seven strikeouts over 7 1/3 frames to win his third straight start and give the Phillies six wins in a row for the first time since Sept. 5-12, 2012.

"We're putting in the work," Phillies manager Ryne Sandberg said. "Everyone's doing their part."

Charlie Blackmon, D.J. LeMahieu and Carlos Gonzalez each drove in a run for the Rockies, who have dropped two straight and 14 of their past 16. Gonzalez drove in Nolan Arenado in the eighth inning with a single and Charlie Blackmon's two-out RBI single in the ninth made it a one-run game.

However, Arenado struck out swinging against Phils closer Jonathan Papelbon to end the game.

"We can leave the ballpark knowing we gave a good effort," Arenado said.

Jordan Lyles, who exited his last start after getting struck in the hand by an Albert Pujols line drive, was tagged with the loss after allowing four runs on seven hits and two walks in six innings.

Chad Bettis looks to shake off a subpar season debut when he starts tonight for the Rockies.

Recalled from Triple-A Albuquerque the previous day, Bettis faced the Los Angeles Dodgers on Thursday and yielded four runs over five innings of a no- decision. He yielded seven hits and walked another four batters, striking out three in a game his club managed to win 5-4.

The 26-year-old righty will make his 10th career start and 39th MLB appearance this evening and has a 1.23 earned run average without a decision in three prior meetings with the Phillies, including one start.

The Rockies have won four of their past six at home against the Phillies.