Qual: Castroneves on top

It was the Brazilian's second consecutive pole in his Marlboro Team Penske Toyota-powered Dallara. But in Chicagoland, the pole isn't much of a concern for drivers, as the event has gained a reputation for close racing in its first three years as an IRL venue. It holds the league record for closest finish - Hornish's 0.002s win over Al Unser Jr in 2002 - and last year's race ended with a memorable three-wide finish involving Hornish, Scott Dixon and Herta.

"We seem to be able to find speed during qualifying at some races," Castroneves said afterwards. "A little bit here, a little bit there. I'm extremely happy about it."

Kanaan can clinch the championship Sunday if he wins and Andretti Green Racing team-mate Dan Wheldon and Team Rahal's Buddy Rice exit early. Kanaan had knocked Rice from the pole spot before he too was knocked down by Castroneves.

"After the morning practice session, we tried a bunch of things," Kanaan said. "We knew 214 was what we could do. I matched my lap time from this morning. I got everything out of my car. I was watching everybody pretty closely in the morning session, so Helio surprised me in qualifying. As soon as he did 214 on the warm-up lap, I knew we were done."

It was only the third pole in 14 events this season for a Toyota-powered car, and all of them have been set by Castroneves.

Dario Franchitti nabbed the fourth spot, just ahead of AGR team-mate Wheldon. A.J. Foyt IV, who hasn't started better than 14th this season, set the sixth-fastest lap in his A.J. Foyt Racing Dallara-Toyota.

Castroneves's team-mate, Sam Hornish Jr, held the pole briefly early in the session before settling into seventh. Vitor Meira, Bryan Herta and Adrian Fernandez rounded out the top 10.