Updated

Chris Capuano was stellar on the mound and shoddy at the plate.

For that, the left-hander was upset with himself after the New York Mets lost to the Colorado Rockies 2-1 on Monday night.

Capuano (2-4) made one key mistake in 6 2-3 strong innings, hanging an 81 mph slider to Chris Iannetta, who broke a tie in the seventh inning with a low liner that just cleared the left-field fence.

The pitcher's performance at the plate, though, left something to be desired. He struck out three times, including once with the bases loaded in the sixth.

"As a pitching staff, we don't want to be an automatic out," Capuano said. "We should be able to at least put the ball in play. It's something I want to work on."

That's simply the way the night went for the Mets, who left 10 runners on base and dropped to 0-5 against Colorado this season — including a four-game sweep at Citi Field last month.

Once again, they struggled to come up with the timely hit. New York is 1 for 16 with runners in scoring position over the last two games.

"It's all about plate discipline," manager Terry Collins said. "Chris pitched a great game, an outstanding game. We had lots of opportunities to get him some help and we didn't get the hit. He really pitched well."

As for Iannetta's homer that barely went over the wall, well, nothing surprises Collins at Coors Field or any other yard with a little altitude for that matter.

"I've spent enough time in here, Albuquerque, Colorado Springs and Salt Lake City to know if you hit the ball on the barrel, it has a chance to go out," Collins said. "I don't care how high it is."

Still, Collins was a bit surprised that Jason Bay's drive in the eighth off Rafael Betancourt stayed in play. Bay hit the ball to straightaway center field and Dexter Fowler hauled it in on the warning track.

"I thought that ball was gone," Collins said. "I thought that ball was going to get out."

Capuano was a hard-luck loser for the second straight outing. He pitched well Wednesday in a 2-0 loss to Tim Lincecum and the San Francisco Giants.

Capuano scuffled with his control early against Colorado, but settled into a groove. He held the heart of the Rockies' lineup — Carlos Gonzalez, Troy Tulowitzki and Todd Helton — to just one hit.

It was the lower part of the lineup that gave him trouble. In the fifth, Iannetta led off with a double and scored on Fowler's RBI single.

"It's great to be in the rotation and going deep into games. I do get a lot of joy out of that," Capuano said. "It was tough to get loose tonight. I struggled with my command.

"Late in the game, I had a mental mistake. ... I was trying to throw a backdoor breaking ball there (to Iannetta) and it stayed up in the middle of the plate right into his swing."

After the game, Capuano was informed of the news involving Mets right-hander Chris Young, who might need season-ending surgery after re-injuring his pitching shoulder.

Capuano has been plagued by arm trouble of his own, going through reconstructive elbow surgery in 2008. His heart went out to his fellow hurler.

"That's too bad," Capuano said. "It just gives you a sinking feeling in your stomach. I know where his head's at. He's such a competitor, such a good asset to this team."

The Mets managed their lone run in the sixth when Carlos Beltran scored from third on Bay's high chopper. Bay reached safely on third baseman Ian Stewart's throwing error and was credited with his fifth RBI.

New York had a threat brewing with one out in the seventh but Daniel Murphy was thrown out at the plate when he tried to score from third on Beltran's grounder to first. Ike Davis grounded out to end the inning.

NOTES: The Rockies snapped their four-game skid. ... New York's top pitching prospect, Jenrry Mejia, will have season-ending Tommy John surgery on his right elbow. He had seen renowned orthopedist Dr. James Andrews for a second opinion. ... Colorado is 8-6 at home this season.