SAO PAULO (AP) -- Helio Castroneves can't count on home advantage against rival teammate Will Power at the Sao Paulo 300 on Sunday.
Castroneves, the IndyCar Series leader, is one of the home-crowd favorites in Brazil. But it's his Penske teammate from Australia who arrives as the favorite to win on the streets of Sao Paulo after capturing all three races at the temporary Anhembi track.
While Castroneves is off to the best start of his career after three straight top-10 finishes, he'll have to get past the "King of Sao Paulo" to improve his chances of staying atop the drivers' standings following Sunday's race.
"We will try to stop him this time," Castroneves said of Power. "But if we can't do that, hopefully we can at least keep the points lead."
There should be even more challengers to Castroneves' lead this time, as three different drivers have won races so far this season. Two of them celebrated victory for the first time - Takuma Sato and James Hinchcliffe. Ryan Hunter-Reay was the other winner.
"There's been a lot of competition this year, even more than in the past, so it's hard to say there's a favorite for Sunday's race," Castroneves said. "But you can't avoid talking about my teammate as the top contender; there's no doubt he has been really successful here in the past."
Power was hardly challenged in Brazil last year, leading the most laps and winning from the pole position. He also dominated in Brazil in 2011 and in the inaugural race in 2010.
But Castroneves hopes things will be different this year in Sao Paulo.
Power has had an unusual poor start to his season on road and street circuits, while Castroneves has been consistently fast and running near the front in all three races so far.
Castroneves enters the home race with a six-point lead over Sato, the winner in Long Beach two weeks ago. Power has only one top-five finish and is eighth in the drivers' standings, 37 point behind Castroneves.
"I hadn't even realized at first but this has been my best start to a season ever," said Castroneves, who is still seeking his first series' title. "I made a mistake in the first race, I should have won that one. But we have been really consistent."
Castroneves was second in the season opener in St. Petersburg, losing the lead to Hinchcliffe after a poor restart in the final laps. The Brazilian finished third in Alabama and managed a 10th-place finish in Long Beach despite having to make an extra pit stop to replace a damaged front wing.
Castroneves is one of only three drivers with top-10 finishes in all races this year.
The three-time Indy 500 winner hasn't had great success in Sao Paulo in the past, but he has two top-five finishes on the Anhembi track. His best finish was fourth last year. In 2011, he was involved in a series of incidents and finished 21st, and in the inaugural race he was fifth.
Being at home, he knows the motivation will be there no matter what.
"Coming to Brazil it's always nice because of the support from the public," he said.