"Really, that was the only pitch I wish I could take back," said Lohse, who allowed three earned runs and five hits with two walks and three strikeouts.
Colorado made it a three-run game on another two-out hit in the third. With Kaz Matsui bolting from first base on a hit-and-run, Matt Holliday skied a popup to shallow right field. Because he first took a step to cover second base, Brandon Phillips was late getting under the ball. Phillips just missed a diving catch as Matsui scored from first base on the RBI single.
Lohse (2-7) was coming off throwing a six-hit shutout on Monday against the Pirates. That outing snapped a six-start losing streak. After he had begun the year with a 1.91 ERA over his first four starts, he had a gaudy 8.59 ERA during the six consecutive losses.
"He's got good stuff," Reds manager Jerry Narron said. "It's a matter of putting it together, and tonight he gave us some good innings."
Coming up with solid performances, back-to-back, wasn't enough consolation for Lohse.
"The bottom line was that we lost," Lohse said. "I went out there and felt like I kept us in the game. The damage was kind of done. They had a pitcher that was throwing the ball well over there. It just didn't work out."
Rockies starting pitcher Jeff Francis retired the first 12 batters he faced in the game. The Reds' first hit off the left-hander didn't come until Jeff Conine's leadoff single in the fifth inning.
"We've struggled a little bit vs. left-handers this year," Narron said.
A little bit? Try a lot. Cincinnati is a National League-worst 7-17 against left-handed starters this season. And the Reds' 22-35 overall record remains the worst in the league.
Francis (5-4) allowed one earned run and five hits and struck out six batters over seven innings. The Reds had a chance to do damage with back-to-back singles that started the sixth, but went down in order after that. They finally got on the scoreboard in the seventh.
After Alex Gonzalez hit a one-out double to left field, he scored on Edwin Encarnacion's RBI double over center fielder Willy Taveras' head.