The Colorado Rockies (50-74) bullpen gave up three runs in the eighth along with the lead, and saw their five game winning streak end as the Chicago Cubs (48-76) earned the 5-3 win yesterday in the Windy City. Game 2 of the three-game series is this morning at 11:05 MT at Wrigley Field (TV: Root Sports).

The three-run eighth inning spearheaded by Brett Jackson's leadoff homer -- and assisted by two errors -- gave the Cubs a the victory at Wrigley Field in front of 31,255.

The Rockies managed three early runs, two on home runs from Chris Nelson and Carlos Gonzalez, who hadn't gone deep in a month. It was the type of game the Rockies have been winning lately, with improved pitching and timely fundamentals. But the normally reliable Matt Belisle (3-5) and the defense deserted them Friday, as they suffered their sixth loss in the last 18 games.

"It's a tough loss, but we can't let that affect us," said Gonzalez, whose third-inning homer was his 21st, but first since July 23 -- a drought of 79 at-bats.

The Rockies entered the eighth with a 3-2 lead. After some decent work from starter Drew Pomeranz (five innings, two runs on homers by Alfonso Soriano and Welington Castillo) and reliever Josh Roenicke, the Rockies put the game in the hands of the normally reliable Belisle.

However, Jackson, the Cubs' first-round pick in the 2009 First-Year Player Draft, tied the game by clubbing Belisle's 1-2 breaking ball for his second home run since being called up from Triple-A Iowa on Aug. 5.

Luis Valbuena doubled two batters later and Joe Mather singled him home for the go-ahead run. The Rockies were in line for at least one out on Josh Vitters' bouncer to third, but former Cub DJ LeMahieu dropped Nelson's throw at second base.

Matt Reynolds replaced Belisle and promptly threw wildly to first trying to retire Anthony Rizzo, which allowed the Cubs to plate an insurance run for a 5-3 lead.

In a matchup of teams in the midst of youth movements, the Rockies showed up with 10 rookies on their roster and the Cubs had eight. The Cubs lead the Rockies by one in number of rookies used this year, 16-15. The Cubs were a little better Friday.

Lately, the Rockies have been able to overcome their youth through decent pitching and execution. The latter escaped them in the eighth on Friday, which made a winner out of Cubs reliever James Russell (6-1). Carlos Marmol pitched the ninth -- overcoming Nelson's one-out bloop double -- for his 16th save.

The collapse robbed Pomeranz of an overdue chance to celebrate. He has now gone eight starts without a win, but at least he was in line for one Friday for the first time since he beat Washington on July 6.

The fastball and proper mechanics that have come and gone during his rookie year -- and second full professional season -- arrived Friday. He walked just one and struck out one. He also showed a good curveball -- a pitch he hasn't mastered in the Mile High atmosphere of Coors Field.

The fifth-inning home runs two batters apart were the only hits against him. He threw strikes on 43 of his 72 pitches.

Pomeranz had been working inside all game and thought he had Soriano jammed, but the famed out-blowing winds at Wrigley taught him a lesson.

Jeff Samardzija yielded a run in a first inning in which the Rockies were aided by shortstop Starlin Castro's error on Jonathan Herrera's grounder, and Nelson and Gonzalez led off the next two innings with homers. However, Samardzija struck out seven in seven innings and held the Rockies to six hits.

It was the type of game the Rockies have been winning lately, almost surprisingly so. Shortstop Troy Tulowitzki hasn't played in the Majors since late May and began his rehab assignment for left groin surgery Friday night. First baseman Todd Helton is out for the year after left hip surgery and outfielder/first baseman Michael Cuddyer also could be gone for the season because of a right oblique strain.

Tickets are available for the Rockies’ next home game at Coors Field vs. the Los Angeles Dodgers on August 27th, and can be purchased by calling (800) 388-ROCK, or click here.

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