Power was followed closely by fellow Team Chevy drivers Tony Kanaan and Sebastien Bourdais.
Castroneves enters Sunday’s race 31 points ahead of Scott Dixon, who will start second.
Helio Castroneves suffers minor injuries after crashing his Brazilian stock car this weekend.
Helio Castroneves continues to lead IZOD IndyCar series points.
Will Power fourth-place finish marked his fourth top-five result of the season and it represented his best finish on a road course in 2013.
Power recorded a lap of 1:05.5359 in the No. 12 Verizon Team Penske Dallara/Chevrolet around the 13-turn, 2.258-mile road course.
Helio Castroneves, who has finished in the top 10 the past nine races, enjoys a 29-point advantage over Scott Dixon heading into the Honda Indy 200 at Mid-Ohio this weekend.
Helio Castroneves continues to lead the IZOD IndyCar Series standings, Will Power has led laps in 10 of the 13 races this season, which is tops among all drivers in the series.
The reigning IZOD IndyCar Series champion set the fastest lap in the IZOD IndyCar Series open test at the Mid-Ohio Sports Car Course in Lexington, Ohio.
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Dario Franchitti was a technical consultant and has a voice cameo in the movie along with Mario Andretti and Will Power.
Helio Castroneves, No. 3 Hitachi Dallara/Chevrolet, finished in second place position on Indy Race 2 on the streets of Toronto.
Sebastien Bourdais gets second podium finish of weekend from successful standing start.
Chip Ganassi’s Scott Dixon had a near perfect weekend on the Exhibition Place street circuit in Toronto. The Kiwi leaves Canada with one pole and two race wins.
Yesterday on the street circuit at the Exhibition Place in Toronto, Franchitti grabbed the pole for today’s first race. In today’s qualifying for the doubleheader event his teammate Dixon set the fastest lap.
Power turned a fast lap of 1:00.0612 seconds, while Castroneves recorded a lap of 1:00.2866 for Saturday’s race
Helio Castroneves continues on top of point standings; Chevrolet maintains the lead in the Series Manufacturers’ standings with eight races remaining in the season.
With an eighth-place finish, Helio Castroneves earned his 10th top-10 result in 11 races this season. Penske teammate Will Power took the checkered flag in the fourth position.
Both Castroneves and Power record top-10 speeds for team Penske at Pocono open test Thursday