Penske Racing president Tim Cindric has tweeted that Castroneves, the second-place driver in the IZOD IndyCar Series championship, will have the engine swapped on his No. 3 Team Penske Chevrolet -- which means that he'll have to absorb a 10-spot grid penalty.
Based on his 13th place result in qualifying, Castroneves would have to start 23rd in tomorrow's race with the penalty.
Castroneves enters tomorrow's race just 21 points behind Ryan Hunter-Reay in the standings.
UPDATE: Helio's PR team has confirmed the penalty.