DENVER -- Rockies third baseman Ian Stewart's game-tying home run in the ninth inning of Wednesday night's 8-6 victory over the Red Sox was -- he hopes, at least -- the end of a slump that the slugger still has a difficult time explaining.

Stewart entered Thursday night's game 7-for-42 (.167) in June. He had been in and out of the lineup while trying to regain his swing, but he went 2-for-4 on Wednesday.

"There wasn't anything wrong with me physically or anything like that," Stewart said. "It's hard to explain.

"I'd see some pitching that I knew I could hit, but I'd let them go by or I'd miss them -- or I'd look for a pitch one place and it would go somewhere else."

Stewart is capable of being streaky, having hit .293 with four home runs in April. Last year, he alternately went through periods of hitting for high power and low average, finishing at .228 but with 25 home runs and 70 RBIs.

After working on consistency and seeing results for this season's first month, Stewart admitted that frustration set in.

"It's something that I hope is at its end," Stewart said. "It was a grind, coming to the park every day and knowing that what should be happening wasn't happening. I'm hoping now I can settle down and just hit."

'No issues' in De La Rosa's rehab start

DENVER -- Rockies manager Jim Tracy said he was thrilled with the progress report he heard from Triple-A Colorado Springs about left-hander Jorge De La Rosa's first rehab start, which came on Wednesday night.

De La Rosa, on the 15-day disabled list with an injured tendon band in the middle finger of this throwing hand, tossed four innings and allowed one run on four hits. He threw 72 pitches, including 48 strikes.

"I can't tell you how happy I am to hear of no issues whatsoever with the finger," Tracy said. "He had no problem in sensation or feeling in any of his pitches. He made sure everybody's aware of the fact that he got an [at-bat], and he hit a bullet."

De La Rosa struck out five batters and issued no walks.

"For the amount of time that he hasn't pitched, to go out there and not walk anybody, that's even more encouraging, knowing how hard it is to get hits off this guy," Tracy said. "If he's not going to create traffic for the opposition, you have to create for yourself. With the type of stuff he has, that makes it real hard for the opposition."

De La Rosa will throw a bullpen session with the Rockies on Friday in Anaheim before his next rehab start with Colorado Springs, scheduled for Sunday.

De La Rosa is 19-9 in the past two seasons combined and was 3-1 with a 3.91 ERA this season before being placed on the DL.

Rox hope walk-off can be springboard

DENVER -- During the Rockies' recent run of successful seasons, there have always been a handful of memorable moments and games that could be considered pivotal turning points.

Could Wednesday's 8-6 win over the Red Sox in front of a sellout crowd -- capped with Jason Giambi's walk-off homer in the ninth inning to bring the Rockies to five games over .500 for the first time this year -- be a game the club looks back on down the road?

"Yeah, why not?" said right-hander Ubaldo Jimenez, who took his first no-decision of the season on Wednesday. "Especially against a team like Boston and facing [Jonathan Papelbon], the best closer in the Major Leagues, it could be a turning point. Everybody is going to be more excited every day, and we know we can come back any time."

Prior to Wednesday's game, the Rockies had been 0-23 when trailing after seven innings. Home runs from third baseman Ian Stewart and Giambi -- a pinch-hitter -- changed that.

"We didn't necessarily have to win every single day like that last year," manager Jim Tracy said, "but we did have moments and games where we trailed by a run or a couple of runs, and because of where we were in the game and what had been done, we came in feeling like we can win the game. There was a mind-set in here just like that."

Herrera filling big shoes for Rockies

DENVER -- Rockies infielder Jonathan Herrera figured he'd have chances to impress when he was called up from Triple-A Colorado Springs on May 31, but the opportunity has turned out to be beyond what he imagined.

Thursday night's finale of a three-game set with the Red Sox was Herrera's 10th start overall and sixth straight. Herrera's opportunity came when shortstop Troy Tulowitzki suffered a fractured left wrist that could keep him out between eight and 10 weeks.

Herrera has made the most of his starts. He entered Thursday night's game with a five-game hit streak and singled in each of his first two at-bats off Boston righty Daisuke Matsuzaka in the series finale.

"When I came up, I realized that I might not play every day, but I could come off the bench as a pinch-hitter or play defense in a double-switch," said Herrera, who moved into the leadoff role, as fellow Venezuelan and childhood friend Carlos Gonzalez moved to Tulowitzki's No. 3 spot in the order. "So now I have the opportunity to play every day. All I can do is play hard and help the team win."

Herrera, 25, whose only previous Major League experience consisted of a 28-game stint in 2008, said he's consciously avoiding thoughts of the future, when Tulowitzki returns.

"I'm trying to get away from that and just take the opportunity, do everything they ask, even if I'm coming off the bench," Herrera said. "Anything is possible if you just play the game, play relaxed and enjoy the moment."

Rockies manager Jim Tracy has confidence in his reconstituted infield. Herrera and Clint Barmes -- who moved from second base to shortstop -- are both rangy, not only on grounders but into the outfield on bloopers. Herrera went into right-center to take a possible bloop hit away from Darnell McDonald in the fifth inning of Wednesday night's 8-6 victory.

"He has tremendous range behind him, and that's very important due to the size of our outfield," Tracy said of Herrera. "The most difficult ball to defend in this ballpark is the ball that is between an infielder and an outfielder if you don't have infield range to close that gap."