Colorado starter Aaron Cook picked up the win. (Chris McGrath/Getty Images)

The Colorado Rockies found enough offence to hang on for a 5-4 victory over the hometown Philadelphia Phillies on Thursday to even their best-of-five National League Division Series at 1-1.

The Rockies jumped out to a 4-0 lead on Phillies starter Cole Hamels, who rushed off to be with his pregnant wife after being pulled for a pinch hitter in the bottom of the fifth, but Philadelphia stormed back in the sixth to make it a one-run game.

Colorado would add a much-needed insurance run in the seventh, and held on for the win as Huston Street picked up the save in a nervy ninth inning that saw the Phillies put the potential tying run on second base.

Hamels (0-1), the reigning World Series MVP, gave up four runs on seven hits, walking none with five strikeouts. It's possible the ace lefty's mind was wandering on the mound before he bolted to the hospital to join his wife, Heidi, who was in labour with the couple's first child.

"It could've bothered him, yes," Phillies manager Charlie Manuel said. "He was concerned about his wife and his child. It's an exciting time, something you look forward to. It was probably on his mind."

Colorado starter Aaron Cook (1-0) fared much better early, but faltered in the sixth. He gave up three runs — all in the sixth — before being pulled, and surrendered seven hits total with two walks and four strikeouts.

"His sinker was downhill and he was really working both sides of the plate," said Rockies catcher Yorvit Torrealba, whose two-run homer in the fourth gave Colorado a 3-0 lead.

Happ hurt

What could be more troubling for Philadelphia is that pitcher J.A. Happ, who was in the running to start Game 3, had to leave in the seventh after only facing only one batter. He took a Seth Smith comebacker off his left knee and was limping after the incident.

The Phillies trainer immediately came rushing out and Happ left the game for Scott Eyre. X-rays on Happ were negative.

"He was trying to stay out there, but he wasn't able to pitch," Manuel said. "I think he'll be fine."

Philadelphia made the Rockies sweat when Jayson Werth hit a solo homer off Rafael Betancourt to make it 5-4 in the bottom of the eighth, after Colorado loaded the bases in the seventh and eighth but could only produce one run.

Street made it interesting in the ninth when he walked pinch hitter Matt Stairs with one out. Cliff Lee, the starting pitcher in Philly's Game 1 victory, came on as a pinch runner and advanced to second on a two-out single by Jimmy Rollins. But Street got Shane Victorino to line out to second to end the ballgame.

Game 3 goes Saturday night in Denver. Jason Hammel (10-8) will start for the wild-card Rockies against a yet-to-be-announced pitcher. Manuel said he'll use Joe Blanton, who worked an inning on Thursday, or Pedro Martinez, who didn't see any action in the first two games. Happ was a candidate before getting injured.

Rockies get to Hamels early

The Rockies picked up the lead early on some good small ball. In the top of the first, leadoff hitter Carlos Gonzalez got on board with a single off Hamels, then stole second with Dexter Fowler up to bat.

Fowler's groundout allowed Gonzalez to advance to third, and he scored when Todd Helton hit into a fielder's choice to make it 1-0 Colorado.

After a quiet second and third inning, the Rockies added to their lead in the top of the fourth. With Helton on first, Torrealba smacked a 1-1 pitch over the wall in left for a two-run homer, putting Colorado up by three.

The problems continued for Hamels in the fifth, when he allowed runners to reach second and third with one out. Fowler again hit a sacrifice to advance the runners, and earned an RBI as Cook easily scored from third to make it 4-0.

Hamels was replaced in the sixth by Blanton.

The Phillies finally got to Cook in the bottom of the sixth. With runners at the corners, first baseman Ryan Howard hit a double to the gap in right-centre, scoring Shane Victorino to make it 4-1.

Cook was pulled after the run was scored, leaving runners at second and third when Jose Contreras entered the game. Contreras struck out Werth but gave up a two-run single to Raul Ibanez to suddenly make it a one-run ballgame.

The Rockies quickly countered in the seventh with another run, but should have had more as they loaded the bases with nobody out.

Fowler hit a sacrifice fly to right, scoring Ryan Spilborghs from third. But that's all Colorado could get as Phillies reliever Eyre held the fort.

With files from The Associated Press