EDMONTON, Alberta - Scott Dixon was surprised, Helio Castroneves was steaming and Will Power continues to lead the IZOD IndyCar Series championship standings though he was thwarted again in seeking his third consecutive victory.

Dixon prevailed in the 95-lap race on the 1.973-mile, 14-turn City Centre Airport circuit courtesy of a black flag issued to race leader Castroneves for blocking on a Lap 92 restart.

Castroneves and Power entered Turn 1 side by side, with Castroneves hitting the apex a car length ahead. As Dixon slipped past Power into second place, race chief steward Brian Barnhart immediately called Castroneves for blocking his Team Penske teammate.

The black flag call was radioed to the No. 3 car, but Castroneves failed to take the drive-thru pit lane penalty. Following the race, he was penalized 20 seconds and placed at the end of the lead lap (10th). A black flag cannot be appealed, according to Indy Racing League rules.

Castroneves overtook Power, the pole sitter, in Turns 1-2 of Lap 78 and recorded his fastest race lap on 79 (1 minute, 2.3139 seconds) to put a 1.5-second gap between him and Power. It appeared that Castroneves would go on to his second victory. His first of the season - at Barber Motorsports Park in mid-April -- derailed Power's bid for a series record-tying third consecutive victory.

But a full-course caution was called on Lap 89 after the No. 78 car driven by Simona de Silvestro ran out of fuel and pulled off course in Turn 7. Castroneves led the field into Turn 1 of the restart, with Power making a bid to regain the lead he had for 76 laps.

Power recovered to finish second, while Dario Franchitti finished third and Ryan Briscoe was fourth. Andretti Autosport's Ryan Hunter-Reay finished fifth.