CHICAGO -- Tyler Chatwood made just one mistake on Thursday, but by the next inning, it hardly seemed to matter.

The Colorado right-hander gave up a first-inning home run and then little else, leading the Rockies to a 4-1 victory over the Chicago Cubs in the opener of a four-game series.

"He's got it in him to pitch a good, solid game," Rockies manager Bud Black said. "Tonight, the key was fastball location, especially down and away to their big left-handed hitters."

Charlie Blackmon went 2-for-3 with an RBI, and DJ LeMahieu added a three-run homer as the National League West leaders (39-23) won their fifth straight and sixth in seven games.

Chatwood (6-7) pitched six innings and allowed one run on four hits. He walked two, struck out four and improved to 3-0 all-time against the Cubs.

Left-hander Jon Lester (3-4) worked five innings of four-run ball for Chicago (30-29), which has lost two straight.

Lester missed out on claiming his 150th victory and now has two losses and a no-decision in his last three outings. He is 1-3 all-time against Colorado.

"We were a little out of the zone today," Cubs manager Joe Maddon said. "The thing about Chatwood was the sinker was that good today. Even though we might have been chasing a little bit low, the ball was really dive-bombing at the end."

Three Rockies relievers -- Scott Oberg, Jake McGee and closer Greg Holland -- took it the rest of the way, allowing just two baserunners and no runs in the final three innings. Holland pitched the ninth to collect his 22nd save.

Kris Bryant's team-leading 14th homer of the season gave the Cubs a 1-0 first-inning lead.

The Rockies replied with four runs in the top of the second -- all coming after two outs.

Tony Wolters and Chatwood singled, and Blackmon doubled to shallow left field to drive in a run. LeMahieu then homered to right for a 4-1 lead.

"That's a really good pitcher (Lester) out there, and luckily he threw one in and I was able to step in the bucket far enough that my barrel got to it, and it worked out," Chatwood said. "Then Charlie got a big hit and then DJ hit a home run which was huge."

After Bryant's homer, Chatwood didn't give up another hit until Anthony Rizzo's single to right with one out in the fourth.

Lester walked one and struck out five while throwing 94 pitches.

"Jon was really good actually," Maddon said. "They hit the one homer, but otherwise he had a pretty good outing."

The Cubs were without shortstop Addison Russell, told to take Thursday off in the wake of allegations of domestic abuse against his wife, Melissa, that surfaced on social media on Wednesday. Major League Baseball is investigating.

NOTES: Colorado two took of three from the Cubs in a May 9-10 set at Coors Field that included a split doubleheader after a rainout the night before. The Rockies also took four of six in the 2016 series. ... The Rockies have the most wins in franchise history to date and the best winning percentage (.623) through 61 games in franchise history. ... Colorado rookie RHP German Marquez (4-3, 4.53 ERA) will start against the Cubs for the second time on Friday. He goes against LHP Mike Montgomery (0-3, 2.21 ERA), a reliever who got the call after RHP Kyle Hendricks was placed on the 10-day disabled list with tendinitis in his right hand. ... Cubs LHP Brett Anderson (lower back strain) was moved from the 10-day disabled list to the 60-day DL. Chicago also called up RHP Seth Frankoff from Triple-A Iowa.