The IndyCar championship will be decided at the season finale at St Petersburg, Florida later this month.
Scott Dixon has been unable to clinch his sixth title at the penultimate race in Indianapolis after finishing in eighth place.
Championship rival Josef Newgarden, who won the opening race of the double-header in Indianapolis, has finished fourth to trim Dixon's series lead to 32 points.
"We tried everything that race. You know we were flat out," Dixon said, after starting from 15th on the grid.
"Interesting day for us. I think we're 32 points out in the lead now.I think we have to be ninth or better come St. Pete so still a lot of hard work here.
"As always the NTT IndyCar series comes down to the final race, even without double points and the lead that we had, over a 100 points at one stage."
Dixon had led by as many as 117 points, but has finished outside the top five in four straight races and has seen Newgarden eat away at his advantage.
"It's nice to still be on the leading side of the points at this stage. It's still a good margin.
"Gives us a little bit of window. You know he (Newgarden) has to get most laps led, he has to get the four bonus points and we have to finish ninth.
"They've been very good in St. Pete too for many years so we're definitely going to have our work cut out."
The Grand Prix of St. Petersburg will be take place early on Monday, October 26 (NZT).