DENVER – Jhoulys Chacin pitched shutout ball into the seventh inning Tuesday night to beat Jon Lester and lead the Colorado Rockies to a 2-1 victory against the Boston Red Sox.

Chacin walked five and allowed four singles in 62/3 innings. Lester, in his first trip to Coors Field since winning Game 4 to clinch Boston’s 2007 World Series title, lost for the first time since April 18 despite allowing just one earned run and six hits, all singles, in six innings.

Boston had won six straight and Lester (8-3) had won eight straight. He was unbeaten in his previous 11 starts.

In ending a personal four-game losing streak, Chacin (4-6) got a big boost from reliever Joe Beimel, who retired pinch-hitter David Ortiz with the bases full in the seventh.

Rafael Betancourt worked the eighth and Matt Belisle pitched a rocky ninth for his first save since July 4, 2005, for Cincinnati at San Francisco. Belisle allowed Mike Cameron’s one-out RBI single before retiring pinch-hitters Bill Hall and Mike Lowell to end the game.

Todd Helton hit an RBI single in the fifth and Ryan Spilborghs’ bad-hop single off Hideki Okajima made it 2-0 in the eighth. It looked as if his routine grounder was going to be an inning-ending double play but the ball took a wicked hop over shortstop Marco Scutaro’s head, allowing Helton to score from second.

The Red Sox twice loaded the bases against Chacin and came up empty.

In the third, Chacin threw three straight balls to Victor Martinez, who finally grounded out to second on a full-count fastball to strand three.

The Red Sox loaded the bases again in the seventh, and Ortiz hit for Lester. The Rockies countered by bringing in Beimel, who got Ortiz to ground out to second base.

Lester only ran into trouble in the fifth, when the Rockies put runners at first and second with two outs.

Helton, mired in a season-long funk, drove a breaking ball into right field to score Chris Nelson, who led off with a single for his first major-league hit.

The Rockies and Red Sox, who fell to 10-3 in interleague play, will continue their three-game series with Ubaldo Jimenez (13-1) facing John Lackey (8-3) tonight.

BOSTON RECALLED outfielder Josh Reddick from Triple-A Pawtucket.

To make room for Reddick, Boston returned right-handed pitcher Robert Manuel to Pawtucket.

Manuel was called up Saturday but never made an appearance with the club.

Manager Terry Francona said the move was made because he needed an extra outfielder. J.D. Drew was still slowed by a strained right hamstring.

Meanwhile, the Rockies activated relief pitcher Huston Street from the disabled list.

“Eventually he will be the guy pitching the ninth inning because that’s what we signed him up for the next three years to do is to pitch the ninth inning,” said Manager Jim Tracy, who will ease Street back into the closer’s role now held by Manny Corpas.

Waiting a week or two for his first save situation is fine with Street.

“The big leagues are the big leagues,” Street said. “It doesn’t matter if you’re throwing in the fifth inning or the 15th inning. Every out matters. Every pitch matters. And you approach it from that frame of reference, it makes pitching the ninth the same as pitching the sixth, pitching the sixth the same as pitching the first.

“The role isn’t, but the mentality is the same.”