Dixon beats Castroneves in Canada

As Castroneves fell nearly six seconds adrift due to a late error, Dixon widened his championship lead to 65 points.

Justin Wilson took his first IndyCar podium in third, with Paul Tracy finishing a remarkable fourth after a charging drive on what is currently set to be a one-off return to the series.

Dixon had qualified fourth and ran there in the opening stages of the race as Castroneves passed his pole-sitting Penske teammate Ryan Briscoe for the lead on lap three while KV Racing's Oriol Servia maintained third.

The points leader got around Servia on the first round of pit stops but appeared to be no threat to the Penske duo, and especially Castroneves, who showed dominant pace as he led by as much as 11 seconds in the middle stages of the race.

"We definitely show ed we had a fast car," Castroneves said. "It was awesome, so much fun. The track really suits my style. We tried not to be conservative; we tried to pull away because, the way the points are, we have not much to lose."

But he did lose his comfortable lead on lap 48 when a full course yellow bunched the field. On the ensuing pit stops, Dixon jumped past both Penske cars into the lead.

"I'd sort of envisioned making a move on Servia early in the race, but it wasn't on." said Dixon. "He was quite a bit slower in race conditions than qualifying, so that enabled me to just stay behind him and save a lot of fuel. When the pit stop came we didn't need as much fuel as he did and so we got around him.

"It was kind of the same thing with the Penskes. I got behind Helio and Ryan, saved fuel and jumped them on the pit stop. That was the key moment of the race."

Given Castroneves' early speed, Dixon expected to have his work cut-out maintaining that lead. Indeed, the Ganassi car was unable to pull away by more than a second and Castroneves was always able to reel him in when he did. But approaching Turn 1 on lap 85, Castroneves locked his right front, slid wide and barely scrabbled around the corner.

"Running behind a guy like that your front tyres go away," said Castroneves. "Plus I was trying to save fuel, so I didn't know whether to try and pass him or play it conservatively.

"But my car was very consistent. What happened on that lap was just weird. I'm not sure, maybe I caught a gust of wind or something, but I braked in the same place and the car just took off."

By the time Castroneves had collected things and regained his rhythm, Dixon was a hefty six seconds up the road. And with the race distance shortened from 95 to 90 laps owing to time constraints, the race for first was effectively over.

"I got the radio transmission that he was six seconds behind." said Dixon. "That's a lot on this track with five laps to go. I think you saw my laps times slowed by about a second after that."

With Castroneves' error ending the battle for the lead, the fraught contest over the remainder of the top positions held the attention instead in the final moments.

After Briscoe spun down the order in a lap 56 restart encounter with Dixon's teammate Dan Wheldon, third place came down to an epic battle between Wheldon, Servia, Wilson (Newman/Haas/Lanigan) and Tracy (Vision) - the latter having charged from 16th on the grid thanks to his own assertive driving and sharp pit work from the Vision/Walker crew.

"Dan, Oriol and I were flip-flopping all race," said Wilson. "We were all saving fuel, and passing each other back and forth as one or the other would make his numbers and then press a little harder."

The battle was ultimately resolved not by Wheldon, Servia, Wilson or Tracy but Marco Andretti. The Andretti Green driver emerged from the pits on lap 81 after stopping for a new nosecone - having damaged his original nose on the left rear tyre of teammate Danica Patrick in an ill-fated overtaking move - only to slide into the grass exiting the Turn 2-3 chicane. He slid back onto the track on the entry to Turn 4 directly in Wheldon's path, whereupon the Ganassi driver braked in avoidance and got hit by Servia for his troubles, as Wilson scooted past both into third.

Wheldon proceeded to drop down the order in his crippled car, enabling first Tracy then a host of others - including a rapidly recovering Briscoe - to get past.

Then Servia slowed with a broken steering arm on the final lap (a legacy of his encounter with Wheldon's gearbox), enabling Tracy to motor past and claim a stunning fourth place finish in car he had never driven before Thursday for a Derrick Walker-led crew that had not worked together since Long Beach.

"I'm just super excited for the team," said Tracy. "They prepared this car in about a week and a half and I gave it a first class effort. With a little more practice and me not sitting on the couch for the last six months, maybe we could do better!"

Briscoe eventually came home sixth (although Dale Coyne Racing's Bruno Junqueira had been on course for the position until his car suddenly slowed with two laps to go) while Wheldon slipped to seventh at the chequered flag ahead of Rahal Letterman's Ryan Hunter-Reay.

Tony Kanaan came through from the back of the grid to ninth and like teammate Andretti and Vision's AJ Foyt IV even briefly led the race thanks to an alternative pit strategy, although it failed to put him into podium contention, partly because of a spin while leading on a restart with 35 laps to go.

Potential winner Will Power (KV) fell out of contention early on with bent suspension - with the same problem afflicting Graham Rahal on the opening lap. Both rejoined after repairs, although Rahal later ended up in the wall after being hit by an out-of-control EJ Viso (HVM).

Other notable incidents in the race included crashes for Vitor Meira, Townsend Bell and Hideki Mutoh, while both Jaime Camara and Mario Dominguez lost wheels as they rejoined after pit stops under yellow.

While hardly a death blow to Castroneves' title chances, Dixon's win - particularly on a day when Castroneves appeared to have the dominant machine - puts him firmly in the driver's seat for the 2008 IndyCar Series title. But he's not celebrating just yet.

"There four races to go and a 65 point lead is not that big when you get 50 points for a win," he said. "But it is a big margin if we're still running at the end of every race. And if we can win one or two more, that'll really put the final nail in the coffin."

Pos  Driver             Team                 Time
 1.  Scott Dixon        Ganassi              1h51:05.7039
 2.  Helio Castroneves  Penske                +    5.9237
 3.  Justin Wilson      Newman/Haas/Lanigan   +   13.4009
 4.  Paul Tracy         Vision                +   28.1462
 5.  Oriol Servia       KV                    +   28.7132
 6.  Ryan Briscoe       Penske                +   36.8816
 7.  Dan Wheldon        Ganassi               +   41.8281
 8.  Ryan Hunter-Reay   Rahal Letterman       +   42.1294
 9.  Tony Kanaan        Andretti Green        +   43.0732
10.  Darren Manning     Foyt                  +   43.3363
11.  Buddy Rice         Dreyer & Reinbold     +   48.3526
12.  AJ Foyt IV         Vision                +   50.1271
13.  Ed Carpenter       Vision                +   57.5967
14.  Bruno Junqueira    Dale Coyne            + 1:01.1009
15.  EJ Viso            HVM                   +     1 lap
16.  Enrique Bernoldi   Conquest              +     1 lap
17.  Marco Andretti     Andretti Green        +     1 lap
18.  Danica Patrick     Andretti Green        +    3 laps
19.  Vitor Meira        Panther               +    6 laps
20.  Mario Moraes       Dale Coyne            +    6 laps
21.  Marty Roth         Roth                  +    7 laps
22.  Will Power         KV                    +   19 laps
23.  Jaime Camara       Conquest              +   23 laps
24.  Mario Dominguez    Pacific Coast         +   40 laps
25.  Townsend Bell      Dreyer & Reinbold     +   43 laps
26.  Graham Rahal       Newman/Haas/Lanigan   +   47 laps
27.  Hideki Mutoh       Andretti Green        +   64 laps