PHOENIX (AP) -- Ryan Roberts did his best Kirk Gibson impersonation, pumping his fist in triumph as he rounded the bases in one of the most amazing moments of Arizona's improbable season, and the Diamondbacks' skipper didn't mind at all.
"Some things rub off," Gibson said. "He deserved to do it."
Roberts' grand slam capped a six-run 10th inning that gave the Diamondbacks the most stunning of their 48 come-from-behind victories this season, a 7-6 triumph over the Los Angeles Dodgers on Tuesday night.
"That was unbelievable," Roberts said. "I've never been a part of something like that. Everything on this team blows my mind."
The Dodgers had scored five runs in their half of the 10th and retired the first two batters in Arizona's half of the inning.
But the Diamondbacks loaded the bases, with the help of reliever Blake Hawksworth 's failure to cover first base, and scored a run on an error. Los Angeles closer Javy Guerra (2-1) came on and walked in a run, then Roberts lined the first pitch he saw over the fence in left field. It was Guerra's second blown save in 23 tries.
"Hawks not covering first opens the door," Dodgers manager Don Mattingly said. "From there anything happens. We basically gave them an extra out and that cost us."
As Roberts rounded the bases he pointed toward the Arizona dugout and pumped his fist again and again in an imitation of Gibson's famous home run trot after his game-ending shot for the Dodgers in the 1988 World Series. He had been planning it all year.
"I've never hit a walkoff home run before in my whole career," Roberts said. "I finally got to do it. I'm glad I remembered" to do the Gibson home run trot.
Micah Owings (8-0) got the victory despite his awful 10th, which included his throwing error that allowed the first run to score.
"He gives up five runs and ends up getting a win out of it," Gibson said. "It's been that kind of year."
The victory keeps alive Arizona's hopes to open the first round of the playoffs at home. For that to happen, Milwaukee must lose to Pittsburgh and the Diamondbacks beat the Dodgers in their regular-season finales on Wednesday night.
Nearly all of the crowd had left after the Dodgers had taken a 6-1 lead in the 10th.
Dee Gordon , who was 3 for 5 with an RBI single, doubled to lead off the inning, then Jerry Sands laid down a sacrifice bunt. Owings, the seventh Arizona pitcher, fielded the ball and threw wild past third base, where he had no chance to get the speedy Gordon anyway.
After Gordon scored, Matt Kemp and James Loney had RBI doubles. A.J. Ellis tripled off the fence in right field, with the ball hitting outfielder Justin Upton in the head. Upton, who had sat out the previous game after being beaned by San Francisco's Tim Lincecum , went into a crouch and was attended to by a trainer, then left the game.
Gibson said he took Upton out as a precaution and was sure he wasn't hurt. He even joked about it.
"At least it didn't bounce off his head and go over the fence," Gibson said. "We got a break there, too, I guess."
After Hawksworth got two routine outs to start the bottom of the inning, he had a 2-2 count on Cole Gillespie when the Arizona batter hit a grounder to first, and the pitcher failed to cover the base.
"I didn't pick up where that ball was until it was too late," Hawksworth said. "I threw the pitch and finished looking down. It was just too late. He runs too well to do that. I can't do that. It was my fault. it should have been an out. You put guys on base stuff like that can happen."
Miguel Montero singled, then Chris Young walked to load the baases. Pinch-hitter John McDonald hit a hard grounder to third that Aaron Miles muffed for an error. That was it for Hawksworth, as Mattingly went to his closer to wrap things up.
Lost in the wild finish was the superb major league debut of Arizona's Jarrod Parker , who didn't allow a run in 5 1-3 innings. Hideki Kuroda, 14 years older than the 22-year-old Parker, blanked the Diamondbacks for six innings.
The Dodgers broke a scoreless tie on Gordon's RBI single off reliever Alberto Castillo in the seventh. Rod Barajas singled with one out, then Jamey Carroll walked. Eugenio Valez, pinch-running for Barajas, took third on a fielder's choice, then scored on Gordon's single. Gordon was out trying to stretch the hit into a double.
Arizona responded immediately. Young drew a leadoff walk from Matt Guerrier in the seventh, then scored from first on Lyle Overbay 's double over the head of center fielder Kemp.
Parker, the ninth overall pick in the 2007 draft, allowed four hits, struck out one and walked one.
Kuroda allowed five hits and struck out five, with no walks.
Notes: Upton was 0 for 3 with two strikeouts and is 2 for 18 in his career against Kuroda. ... The Diamondbacks are scheduled to send LHP Joe Saunders (12-12, 3.58 ERA) to the mound Wednesday, while the Dodgers go with LHP Ted Lilly (11-14, 4.12). ... Gibson said the team will have Thursday off, then work out Friday in whatever city that will host the division series opener. ... If the Diamondbacks and Milwaukee finish tied in the standings, Arizona holds the tiebreaker by winning the season series 4-3.