MILWAUKEE -- Mark Reynolds wasn't expecting to be the Colorado Rockeis' Opening Day starter at first base, but given the opportunity the veteran made the most of it.
Reynolds homered, doubled and drove in three runs as the Rockies opened the season with a 7-5 win over the Milwaukee Brewers on Monday at Miller Park.
Reynolds batted .282 for the Rockies last season but came back on a minor league deal during the winter. He posted a .273 average in Cactus League play, but when Ian Desmond was lost for at least the first month with a broken hand, Reynolds got the nod.
"I didn't expect this role right away, obviously," said Reynolds, who spent the 2014 season with Milwaukee. "Unfortunately, Ian got hurt. You know, you always got to be ready. You got to be ready to contribute and I was able to do that today."
Reynolds reached four times for the Rockies, who erased a one-run deficit by capitalizing on two late errors by the Brewers and got four scoreless innings from their bullpen.
Gray allowed five runs and five hits -- all of them in the fifth inning -- while walking two and striking out seven.
"It's great to see our team come back like that and fight," Gray said. "They picked me up. I need to do the same."
Brewers starter Junior Guerra only lasted three innings. He allowed just two runs on a hit but had to leave the game in the bottom of the third when he strained his right calf running out a sacrifice bunt.
"I put the bunt down, took the first step, went to take the second step, it felt like someone hit me right in the calf," Guerra said through team interpreter Carlos Brizuela. "When I tried to take another step, it just felt like something pulled there, and that was pretty much it."
Guerra was placed on the disabled list after the game but is expected to miss more than just the next 10 days.
"It's a big blow, for sure," Milwaukee manager Craig Counsell said. "It kind of starts the process of what we've preached in spring training. It's not going to be 25 guys, it's not going to be five starters, it's not going to be eight relievers. It's going to take more than that and we're going to start seeing that tomorrow."
Left-hander Tommy Milone took over for Guerra in the fourth and allowed the Rockies to double the margin with three hits.
Gray retired the side in the fourth but allowed a single, a walk and a base hit to open the fifth, loading the bases for Villar, who made it 4-2 with a double to the gap in left. Eric Thames tied it up with a two-bagger to right, bringing Gray's day to an early end.
Travis Shaw gave Milwaukee the lead with a third straight double, scoring Thames.
With Jhan Marinez (0-1) on, Colorado tied the score in the seventh when Reynolds scored on a fielder's choice. A throwing error by Milwaukee catcher Jett Bandy let Tony Wolters come home with the go-ahead run.
The Brewers still had a chance to tie it up in the eighth, putting two on with nobody out against Adam Ottavino, but couldn't cash in as Ottavino escaped by striking out the side.
"I was embarrassed by how I threw to the first two hitters," Ottavino said. "Once I had two outs, I was like 'I can't stop now. I got to get this guy.'
"I just let it all out, got that last strike. So, I was excited."
Colorado added an insurance run in the ninth on a pinch-double by Alexi Amarista before Greg Holland overcame a leadoff walk for his first save of the year.
NOTES: Brewers RHP Junior Guerra's strained right calf cut short his first career Opening Day start. He was placed on the disabled list and the team will make a corresponding move Tuesday. ... Both teams were featuring nine players on an Opening Day roster for the first time in their careers. ...... RHP Greg Holland worked a scoreless ninth inning for his 146th career save. ... Former baseball commissioner Bud Selig threw out the ceremonial first pitch. Selig founded and owned the Brewers until 1992. He will be inducted into the Hall of Fame this summer.