LOS ANGELES -- A 12-2 win over the Dodgers on Saturday highlighted some role changes in the middle of the Rockies lineup.

Carlos Gonzalez, who twice walked in front of Troy Tulowitzki, is playing leadoff man from the No. 3 spot.

"I'm trying to be a leadoff guy for him," Gonzalez said. "No matter what."

Tulowitzki, who twice homered after Gonzalez walked, is playing Kelly Leak, the Harley-Davidson riding superstar -- the fictional one, from the movies.

"I don't have words to describe it," manager Jim Tracy said. "Kelly Leak, maybe. Kelly Leak in 'The Bad News Bears' -- he was on a tear like that. That's the one guy I can think of."

Tulowitzki's two-homer day gave him 14 home runs in his past 15 games. According to Elias, that ties him for the modern-day record in a 15-game span with just two others: Albert Belle in 1995, and Barry Bonds during his record-setting tear in 2001.

Most important to the Rockies, they pulled to within one game of the National League West-leading Padres and are now half a game behind the second-place Giants. They also kept pace in the NL Wild Card race, remaining 2 1/2 games behind Atlanta.

For Tulowitzki, the timing's the thing.

"It's awesome," Tulowitzki said. "I think the timing of it is what definitely makes me a lot happier with it. The timing of it, coming down the stretch here, is huge for our team. If you had to pick one time, it'd definitely be now."

Tulowitzki hit a two-run homer to left off John Ely in the first inning, mirroring the laser of a homer he hit in the same inning on Friday.

His first at-bat took four pitches. It took Tulowitzki two pitches to hit his 30th double of the season in the third inning, on a line drive hit so straight that it fooled Matt Kemp in center and sailed beyond him.

Tulowitzki didn't wait at all in his third at-bat in the fifth, jumping on the first pitch for a line-drive, two-run homer to center that gave Kemp no time to even reach the wall.

"That guy is locked in," Ely said. "It's a little frustrating to watch him get that pitch out of the park. He's the guy we're focused on to not let beat you, and he ends up doing just that. It's frustrating. He had a heck of a day off me today."

Tulowitzki has 26 home runs and four multi-homer games this season. Each of those multi-homer games have come in his past 10 games, two of them in his past three. His first home run on Saturday gave him the club record for most home runs in any calendar month. Matt Holliday held the mark previously with 12; Tulowitzki's at 14, and there are 11 games left in the month.

Tulowitzki also has 33 RBIs in September, putting him one away from tying Holliday for the most ever by a Rockies player in September. In his past 15 games, Tulowitzki's hitting .377 (23-for-61).

"I might not play better my entire career," Tulowitzki said. "It's something that I'll always remember."

Tulowitzki's been just as strong defensively, too. He leads NL shortstops with a .596 slugging percentage and a .985 fielding percentage, and if he maintains those leads, he'd be the first shortstop to lead the NL in both categories since the Pirates' Jay Bell in 1993.

Jhoulys Chacin was the benefactor of the romp. He tossed seven shutout innings, allowed eight hits, walked none and struck out two. He worked out of a bases-loaded, one-out jam in the fifth when Ryan Theriot hit into a double play. It was a bounce-back start for Chacin, who lasted just four innings in his last outing.

"My fastball was real good," Chacin said. "That's why I didn't walk anybody. ... You've got to love that they give you a lot of runs. You pitch more relaxed."

Tulowitzki didn't make an out until a seventh-inning grounder. He came up with the bases loaded in the eighth, and even though the Dodgers' deficit was already 7-0, Los Angeles pitching coach Rick Honeycutt went to the mound to meet with reliever Jeff Weaver.

Walk him? Hit him? Neither. They pitched to Tulowitzki, and got a foul pop out. What the Rockies showed afterward was that this run they're making at the division title isn't a one-man show.

After Todd Helton walked to force in a run, Melvin Mora hit out the first pitch for a grand slam, the fifth of his career and second of the season.

"The thing we're doing right now that was missing earlier in the year," Tracy said, "[is] creating opportunities like we have for ourselves, but then once we get them, capitalizing."