updated 8:49 p.m. ET July 26, 2008

EDMONTON, Alberta - Everyone has at least one embarrassing moment they’d like to forget. Scott Dixon has one he wants to remember.

After a lightning quick pit stop by his Chip Ganassi Racing crew helped him to his fifth IndyCar Series victory of the season Saturday on the temporary airport circuit at Edmonton, Dixon’s gaffe earlier this month at Watkins Glen was clearly on his mind.

“I gave myself a bit of a kick in the bum after what I did at Watkins Glen,” said Dixon, who spun himself out late in that race, finishing 11th and losing valuable points instead of contending for another win.

Dixon, the 2003 series champion, lost the 2007 title to Dario Franchitti when he ran out of fuel on the last lap of the last race. So the series leader remains wary with four races to go, and the mistake at The Glen doesn’t stray far from his mind.

“I think we got remotivation for myself and for the team,” he said. “And you know we can’t lose the championship now because, if I do, it will be because of that race.

“It makes you really understand that it’s not that easy. You definitely can’t let your guard down. It maybe helps you zero in a little more, so it’s maybe a good thing, even though we lost a few points.”

The victory on the challenging 1.973-mile, 14-turn Edmonton track was another big step toward his second IndyCar championship. And he did it by holding off Helio Castroneves, his closest pursuer in the championship.

Castroneves, still looking for his first win of the season, kept the pressure on Dixon lap after lap late in the race, trying to force another error. But it was Castroneves who nearly slid off course on worn out tires six laps from the end, allowing the New Zealander to cruise to the checkered flag.

“I’ve got to thank the team,” Dixon said. “We were struggling at the start of the weekend. We were probably at best about 11th. So, to come through is simply not what we expected. But my guys nailed that (last) pit stop and we got that lead and we were going to be unstoppable.”

Castroneves led a race-high 35 laps and appeared to have the best car in the 27-car field most of the day. But Dixon, who had been running third behind Penske Racing teammates Castroneves and Ryan Briscoe, got past both of them during a pit stop under caution on lap 51.

Several other drivers, on different strategies, stayed on track and moved ahead at that point, but Dixon eventually inherited the lead when Tony Kanaan pitted on lap 62. The Indianapolis 500 winner then led the rest of the way.

Castroneves did his best to catch the leader until he locked up his brakes and skidded through turn one on lap 86. He recovered in time to stay in second, but fell too far behind to make another run in the race, scheduled to go 95 laps but cut four laps short by a 1-hour, 50-minute time limit.

“Not only did he not make any mistakes, but he did what he had to do today,” said Mike Hull, team director for the Ganassi team. “Scott drove a good, patient race with an Indy 500 champion like Helio behind him. That’s a tough thing to be doing when that guy fills your mirrors.”

Castroneves agreed.

“I was doing everything I could, pushing, putting pressure (on Dixon) until my tires just gave up,” said the frustrated and still winless Castroneves after finishing second for the seventh time this season. “You know, he never made a mistake.

“I don’t know what to do. I’ll just keep working hard. It ain’t over yet. It ain’t over yet.”

Dixon, who led only the final 30 laps, began the day 58 points ahead of Castroneves and now leads the Brazilian by 65 heading into the race at Kentucky Speedway in two weeks.

Dan Wheldon, Dixon’s teammate, lost ground when he and Oriol Servia collided late in the race, finishing seventh. The Englishman is third in the standings, 115 points behind Dixon.

It was the first IndyCar race at the former Champ Car venue.

Justin Wilson, one of nine drivers making the transition from the defunct Champ Car World Series to the newly unified IndyCar Series, finished third. Another former Champ Car star, Paul Tracy, making only his second race start of the season, finished fourth, followed by former teammate Oriol Servia and Briscoe.

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