HOUSTON -- Helio Castroneves and Scott Dixon -- the top two IZOD IndyCar Series championship contenders -- will start on Row 1 for Race 2 of the Shell and Pennzoil Grand Prix of Houston.

The starting grid was set by entrant points, in accordance with Rule 8.1.10.1(b) of the IZOD IndyCar Series rulebook, as a rainstorm washed out the 30-minute morning qualifying session on the 1.634-mile, 10-turn circuit carved out of a parking lot at Reliant Park. NBC Sports Network will broadcast the 90-lap race at 1 p.m. (ET).

The last time qualifications were canceled because of weather was 2009 at Kentucky Speedway (Dixon sat on the pole).

Click it: Starting lineup || Dixon wins Race 1

Dixon, who won Race 1 on Oct. 5 to close to eight points of the front-running Castroneves in the championship chase, will start on the outside of Row 1 for the standing start.

Castroneves' No. 3 Team Penske car led in entrant points (486-452) over Dixon's No. 9 Target Chip Ganassi Racing car entering the doubleheader race weekend. He does not receive a bonus point for starting from the pole.

"If we were at a typical road course (qualifying) it wouldn't have been an issue with this amount of rain, but street courses seem to puddle a lot," Dixon said. "We probably would have liked to qualify; it seems Helio is struggling a bit this weekend. To have that separation the grid similar to yesterday would have been nice."

Dixon started third and Castroneves qualified a season-low 21st and finished 18th in the 90-lap Race 1.

"People's speeds are different from how the points have lined up so it should make for a really interesting race," Dixon added.