Wolters hit a game-ending sacrifice fly with the bases loaded and Colorado scored twice in the bottom of the ninth inning to rally past the Baltimore Orioles 8-7 on Sunday.
"It was an important win. We've got to start winning series and it was a good series win," Arenado said. "It would have hurt losing this series."
It appeared Baltimore would win a series for the first time in a month before Colorado came back in the ninth. The Rockies loaded the bases on two singles and a walk, and Ian Desmond battled Mychal Givens in a nine-pitch plate appearance before drawing a walk to tie it.
"He kept fouling pitches off," Givens said. "I thought I can get him on a 3-2 slider, but he laid off of it."
Wolters jumped on the first pitch and hit a fly to left to score pinch-running pitcher Jeff Hoffman with the winning run.
"I was praying, blowing air at it a little bit," Wolters said. "I knew Hoff was pretty fast. I knew he could get there in time."
Wolters' three hits tied a career high and helped the Rockies take two of three in the interleague series -- a rare Baltimore visit to Coors Field. The major league-worst Orioles (16-37) have dropped eight of nine and haven't won a series since April 22-24 against the White Sox.
"We put ourselves in position and we had the lead and we just didn't get it done," Baltimore manager Brandon Hyde said.
Baltimore scored three runs in the seventh and three more in the eighth to rally from a 5-1 deficit.
Arenado's two-run shot gave Colorado a 3-1 lead in the sixth and set the table for Marquez's two-run triple. With two outs, Desmond and Wolters singled and Marquez hit a ball off the wall in right-center against a pulled-in outfield. He trotted into third without a throw for the first triple of his career.
Marquez also was credited with an RBI on a sacrifice bunt in the fifth.
Baltimore strung together five hits in the seventh to get to 5-4. Mancini's error in right field in the bottom of the inning made it 6-4.
Rockies: OF Charlie Blackmon did some on-field activities but was out of the lineup for the third straight game with a calf strain. Blackmon was removed from Thursday's loss at Pittsburgh after fouling a ball off his calf.
Marquez has a hit and an RBI in four straight games and became the 11th Colorado pitcher to hit a triple. He thought he hit it out and had to speed up around second to get to third.
"I thought it was gone but I had to run," he said.
He is hitting .227 this season and has impressed his teammates with his batting style.
"His head barely moves," Arenado said. "It never moves. It looks like he has all this movement but his head never moves. As hitters, you watch that."
CLIMBING THE LIST
Arenado's home run was the 201st of his career and tied him with Dante Bichette for fifth in club history. Arenado hit four home runs in the series, including two on Friday night.
"When Nolan's swinging well he carries the torch," Rockies manager Bud Black said.
Orioles: RHP Gabriel Ynoa (0-1, 5.60 ERA) is scheduled to make his first start of the season Monday afternoon when Baltimore returns home for a three-game series against Detroit.
Rockies: RHP Jon Gray (4-4, 4.62) gets the start to begin a four-game series against Arizona on Monday.
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