DENVER -- Just when it seemed he had been overcome by the dog days of the season, the Rockies’ Ryan McMahon bit back Sunday afternoon.

After a tired-looking 0-for-13 in his last six games, McMahon parked his 21st and 22nd homers, and in between singled in what seemed to be an important run in the seventh. Callup Josh Fuentes, on a three-hit day, provided iron-clad insurance later in the seventh with a three-run shot as the Rockies completed a three-game sweep with a 10-5 victory at Coors Field.

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McMahon admitted some fatigue. He is 130 games into his first year as a Major League regular, usually at second base although he played third to spell Nolan Arenado on Sunday. But he is more than holding his own. After his two-homer performance, his 80 RBIs are tied with Trevor Story for second on the team, behind Arenado’s 116.

“I definitely won’t be too disappointed, but me being me, I’ve always got to be working on something because you’re always trying to get better, find a way to improve,” McMahon said. “I’ll sit down at the end of the year and try to figure out how to be a better, more consistent player.”

One area of improvement is in strength. McMahon reported to Spring Training around 210 pounds, with the idea that he would lose some 5 to 10 pounds to accommodate the move to second base from first base, where he played primarily last year. But after Saturday night’s game, he weighed in at 192.

“One thing I’m really not proud of is I’ve lost like 18 pounds,” McMahon said. “I was hoping to stay at 200-205. But it’s happened gradually, so it’s not like an immediate drop. But I need to figure out what happened.”

Manager Bud Black did not start McMahon the previous two games. Yes, the Padres started left-handers Joey Lucchesi and Eric Lauer, but McMahon had a respectable .271 batting average left-on-left. Fatigue, however, was the real issue.

Even though he bounced between the Rockies and Triple-A Albuquerque last season, and did well enough to earn postseason playing time, he played in just 91 Major League regular-season games. He didn’t have the concentration of playing time or responsibility that he earned this year.

“It’s a long season, from the middle of February to the first of October, and hopefully next year beyond,” Black said. “You have to learn how to go through it, and he’s learning. He hasn’t done this at this level. The Minor League seasons are a month shorter, Spring Training starts later, there are not the demands on you physically and mentally. Players react differently to that intensity and it wears you out. And he’s learning that.”

Rest did him good Sunday.

McMahon was a tick late but drove Padres starter Cal Quantrill’s 2-2, 95.1 mph fastball into the left-field bleachers. The difference was one run in the seventh when he took an Andres Munoz pitch toward the left-field line for an RBI single. In the eighth, he victimized Robbie Erlin -- left-on-left with a pull shot into the Rockies’ bullpen.

Even with the wear and tear, McMahon has stayed mentally sharp enough. In addition to feeling fresher, he was able to correct some habits that led to his slump.

“There were a couple of things with how I was seeing the ball,” he said. ‘I wasn’t really confident in what I was seeing, so my swing got a little bit long and a little slow.

“When you see me doing that [drive balls away and to the pull side], my swing is in a good spot. For me, it’s a good day, build off that.”