DENVER -- The Milwaukee Brewers needed six weeks and every run to win consecutive road games.
"It's unbelievable," closer John Axford said. "Things weren't looking too great in the first two games and it's awesome to come out of here with a split."
"Getting the split's huge," Marcum said. "Hopefully we can keep it going in Arizona and have a good series out there."
It wasn't an easy finish for the Brewers or Axford, who got his 25th save after his second straight nail-biting ninth inning.
Jonathan Herrera reached on an error by shortstop Josh Wilson and scored on Ty Wigginton's double to right to make it 4-3. Carlos Gonzalez grounded out to third for the first out, pinch-hitter Mark Ellis struck out looking and Jason Giambi followed with a walk.
"Run scoring and a guy on second with nobody out, that's not the way you want to start out," Axford said.
Troy Tulowitzki struck out on three pitches to end the threat.
"We can't give Giambi anything he can hit out of the ballpark, even though you don't want to pitch to Tulowitzki either," manager Ron Roenicke said. "We'll throw it in tough places and if they swing and get themselves out, that's good."
Marcum (8-3) was cruising along until he gave up a leadoff homer to Giambi in the bottom of the sixth. He went to a 2-0 count on Tulowitzki when a Brewers' trainer and Roenicke came to the mound to talk with Marcum. Marcum threw a few warmup pitches before being replaced by reliever LaTroy Hawkins.
Marcum said he was injured when he landed on his right shoulder after throwing out Dexter Fowler on a bunt attempt on the last play of the fifth inning.
"I landed on the backside of my shoulder and I jarred something in my back a little bit," he said. "It's a little stiff right now, but I don't think it's anything to be too alarmed about. Keep doing the treatment and be ready the next time out."
Marcum allowed two earned runs and four hits, struck out four and walked two in five-plus innings.
Milwaukee took the lead for good in the fifth and chased Rockies starter Aaron Cook (0-5). Prince Fielder drew a one-out walk, Weeks singled and George Kottaras followed with a double to left to score Fielder. Weeks was thrown out at home on the play, allowing Kottaras to advance to third.
McGehee knocked in Kottaras with a single and came home on Wilson's double to make it 3-1.
Matt Belisle relieved Cook and got the final out of the inning.
"I felt all right but I'm tired of losing," Cook said. "I got three pitches up in the zone in the fifth inning and those were the only bad ones that I made. I gave up those two runs and it ended up costing us the game."
Giambi had two hits, including a homer, and Seth Smith also had two hits for Colorado.
Giambi's 10th homer, into the third deck in right field, made it 4-2 in the sixth. The Rockies threatened for more against Hawkins, but Herrera grounded out to second with runners at first and third to end the rally.
The Brewers scored first when Weeks led off the second with a double, moved to third on Kottaras' ground out and scored on McGehee's sacrifice fly.
The Rockies tied it in the fourth when Fowler scored from second on Smith's single off Weeks' glove.
OF Ryan Braun was held out of the lineup with tightness in his left calf and hamstring but pinch hit in the ninth. Manager Ron Roenicke said Braun could play Monday at Arizona. ... Giambi's homer was the second one hit into the third deck at Coors Field this season.