The Rockies are within a win of matching the franchise record of 11 consecutive victories set from Sept. 16-27, 2007.
Jason Marquis limited the Mariners to a run and seven hits in seven innings, but was denied the decision. He also had an RBI with a bases-loaded walk for the Rockies' first run in the second inning.
The start of the game was delayed 42 minutes by rain.
Working on a pitch count limit of 60, Brandon Morrow worked the first three innings, allowing a run on three hits, fanned four and walked four. Morrow replaced Erik Bedard, who manager Don Wakamatsu announced Friday would miss this start due to left shoulder inflammation.
Chris Jakubauskas took over in the fourth inning and worked three scoreless innings. Lowe gave up two runs on one hit in the Colorado eighth.
Adrian Beltre was 3 for 4 with a pair of two-out doubles and an RBI single.
Colorado's eighth began with Troy Tulowitzki's swinging bunt that Lowe fielded, but he threw the ball into right field to put Tulowitzki on second base. Tulowitzki beat Lowe's throw to third on a fielder's choice bunt by Carlos Gonzalez.
Iannetta's fly ball to right scored Tulowitzki. Two batters later, Barmes drove in Gonzalez with a fly ball to center.
Morrow issued a two-out walk to Marquis with the bases loaded in the Colorado second to put the Rockies ahead 1-0. Morrow ended the inning by getting Dexter Fowler to roll out to first.
Seattle put together another two-out threat in the seventh inning when Suzuki reached on a bunt single and Branyan walked. Marquis escaped by getting Beltre to ground out to shortsop.
Helton broke the 1-1 tie in the Colorado seventh with a broken-bat single to right to score pinch-hitter Seth Smith, who led off the inning with a single. Hawpe doubled off the wall in center, scoring Helton and giving the Rockies a 3-1 lead.
Lopez didn't let lead last long, tying the game at 3-3 with his ninth home run of the year. He followed a leadoff walk to Ken Griffey Jr. with a line drive home run over the left field wall off Corpas.
Mariners RHP Roy Corcoran, coming off a rehab assignment at Triple-A Tacoma, was activated him from the disabled list. ... Seattle's Ken Griffey Jr. made only the second start of his career in left field and his fourth start in the outfield this season. ... The Rockies have put any plans for a RHP Taylor Buchholz's rehab on hold after his bullpen session was shut down after 17 pitches when he developed some discomfort in right elbow.