HOUSTON -- Scott Dixon is now larger than expected in Helio Castroneves' IndyCar Series rear-view mirror.
Dixon won the first leg of this weekend's Shell and Pennzoil Grand Prix of Houston at Reliant Park with Castroneves finishing 18th.
Castroneves entered Saturday with a 49-point lead, but the unforeseen swing reduced the spread to eight with two races left.
"(Saturday) could have only been better if we had (won) the pole," Dixon said. "You hope for days like this ... but in reality they never come."
Castroneves kept repeating the same things to himself and anyone who willing to listen.
"We're still leading," he said. "We're still leading."
Maybe not for long. Next up is Sunday's second race here. The green flag waves at 1:30 p.m. ET on NBC Sports Network. The season ends Oct. 19 at Auto Club Speedway in Fontana, Calif.
Dixon will be favored to win Sunday because he swept the doubleheader at Toronto in July. Castroneves will have his work cut out for him.
The pressure is certainly on Castroneves, who is bidding for his first series title. Dixon won IndyCar's championship twice, in 2003 and 2008.
That wasn't the only story of the day. Simona De Silvestro posted a career-best second, becoming the third woman in IndyCar history with a top-three finish. Danica Patrick is the only woman to have won an IndyCar race. Sarah Fisher finished on the podium twice in her career, including a second at Homestead-Miami Speedway in 2001.
Justin Wilson finished third with Simon Pagenaud fourth and Josef Newgarden fifth. Newgarden has finished second and fifth in the past two races.
Pagenaud remains in the championship hunt; he's 50 points out of the lead. The most points a driver can earn in a race is 53, which means there are 106 still to be won this season. Like Castroneves, Pagenaud has never won an IndyCar title.
Dixon won his 33rd career race, most among active drivers. He is just one win behind Al Unser Jr. for sixth place all time.
Castroneves was in trouble most of the day, qualifying 22nd in the morning and slowing on Lap 23. The problem there was the gearbox, and the Team Penske crew did quick work to get the car back on the track within eight minutes. But the damage was done.
Charlie Kimball and James Hinchcliffe each had problems at the start of the race, with Hinchcliffe's leading to more problems.
For starters, Kimball's clutch wouldn't engage on the first standing start, forcing IndyCar to abort it. On the second try, Hinchcliffe seemed to have a clutch problem, and his car stopped after initially moving.
Two cars behind him swerved to miss him, but Ed Carpenter, who started on the last row, could not, in part because his view was temporarily blocked.
"One of the cars I was following (Tristan Vautier) dodged to one side and I tried to dodge to the inside but I clipped Hinch's car," Carpenter said.
Carpenter's car swiped the left rear of Hinchcliffe's car, with debris scattering as Carpenter's car spun around.
Neither driver was hurt, but Hinchcliffe was upset, apparently with his team.
"I know what happened; I don't want to talk about what happened," he said on the television broadcast, adding that blame "is all over the place."
Takuma Sato won the pole in an abbreviated morning qualifying session, but it was noteworthy because it was the first for his team, A.J. Foyt Racing, in the series since 1999 (Billy Boat at Atlanta Motor Speedway). Houston also is Foyt's hometown.
Sato then had trouble in the race, starting with a cut tire during the initial caution. Later, his radio failed and then he hit the tire barrier in Turn 3.