Helton skied a 418-foot, two-run homer to right with two outs in the ninth inning to give the Rockies a thrilling, 9-8 victory over the Dodgers that gave them a doubleheader sweep and moved them into a tie with Los Angeles in the crowded National League Wild Card chase.
Helton's dramatics, coupled with a 3-1 victory in the opener behind Jeff Francis' career-high 10 strikeouts, meant the Rockies gained a half-game and are 4 1/2 games behind the NL Wild Card-leading Padres with 11 games to play.
"I don't know when I'll come off that high," said Helton, his heart still pounding. "That's hard to explain. It's just one of those things. It was ... just to be in that moment, it was unbelievable."
The Rockies entered the ninth trailing by a run and facing closer Takashi Saito (1-1), who had held them to 0-for-14 with two walks this season. But Matt Holliday, whose two-run shot in the fifth off David Wells was his 100th career homer and 200th hit of a Most Valuable Player-caliber season, singled with two down to give Helton his chance.
Helton sent a Saito slider over the right-field wall to send a Coors Field crowd of 23,282 into elation.
"Choosing slider wasn't bad, but it just went into the zone," Saito said through an interpreter.
The normally stiff-legged Helton dashed the bases almost fast enough to catch Holliday, who had stopped between second and third to celebrate before making his trip home. Helton flung his helmet almost as high as his homer traveled, and leaped into a mass of giddy teammates.
The Rockies had lost two out of three over the weekend to the Marlins. But suddenly, the playoffs -- not to mention finishing ahead of the Dodgers in the standings for the first time since entering the Majors in 1993 -- are worthy goals again.
Bridging the standings gap will be difficult, but the opportunity to do so is a dream for Helton, who debuted in 1997 with the last Rockies team that had a shot in September.
The winning homer was the 301st of Helton's career. After the homer, fans stayed on their feet, cheering a camera shot of No. 17 in the dugout, then reached a new noise level when he emerged for interviews.
Helton has hit .395 (32-for-81) over his last 22 games to keep the Rockies in the race.
Have a question about the Rockies?
E-mail your query to MLB.com Rockies beat reporter Thomas Harding for possible inclusion in a future Inbox column. Letters may be edited for brevity, length and/or content.
After hitting No. 300 on Sunday, he received the first curtain call of his stellar career. Now it's three games and two curtain calls.
This is no longer a dream.
"When you hit a home run and the game doesn't matter, you just run the bases, give your teammates a high-five," Helton said. "But when you're in a situation like that, why do you want to try to keep your emotions in? It's an amazing win for us."
Manager Clint Hurdle said, "I've watched him play a long time and I'm happy for him. We talked the other day about what he's meant to this organization and what he's meant to this team. He's put it in another gear this month."
Starter Mark Redman pitched well enough through five innings for a 5-4 lead. But James Loney's sixth-inning homer off Matt Herges and Russell Martin's eighth-inning shot off Jorge Julio were keys to the Dodgers building an 8-5 lead.
However, Ryan Spilborghs' two-run homer off Jonathan Broxton in the eighth set up the ninth. Recent callup Ryan Speier (1-1) rescued the bullpen with a perfect top of the ninth.
"That was the most fun I've had in baseball, probably ever," Spilborghs said of the comeback. "My throat still hurts right now from screaming like a bunch of kids."
It came on the heels of 6 2/3 standout innings from Francis, who surpassed Shawn Estes' 15 wins in 2004 for most in club history by a lefty, and needs one to match the club record shared by Kevin Ritz (1996) and Pedro Astacio (1999).
"There's more we're trying to do here," Francis said, shifting the focus from his accomplishments.
Francis rebounded from a rough last outing -- eight runs in 3 1/3 innings of a road loss to the Phillies -- by holding the Dodgers to six hits and one run, a homer by Olmedo Saenz.
The Rockies scored twice in 5 1/3 innings against Dodgers starter Chad Billingsley (11-5).
Pinch-hitter Joe Koshansky's RBI double, for his first Major League hit, in the seventh provided breathing room for Manny Corpas, who is perfect in 15 save chances since being named closer just before the All-Star break.
Thomas Harding is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.