Kiwi Indycars star and championship leader Scott Dixon holds a 26-point advantage over Alexander Rossi heading into this weekend's penultimate round in Portland but he isn't worrying about mathematics just yet.

With a double points race to finish at Sonoma Raceway in a fortnight, Dixon feels he needs to just race as hard as ever and leave the calculator behind as he bids for a fifth career title.

"I think we have to treat each race as a normal race," Dixon told "You've got to go in there with the expectation of winning, not trying to finish second and so on.

"The worst thing you can do in this situation is points-race. Getting us to this point are things we've done naturally each race, so we have to continue with that strategy."


With double points on offer in the final round it is almost certainly going to come down to a final race shootout for championship glory.

"It can hurt you, for sure," Dixon said. "But it can also help you. We were on the receiving side in 2015 in the last race, but we also had a horrible Indy 500 that year with a crash. So both of those [double points] races kind of even themselves out over time. There is talk of possibly changing the system in the future, but for now it is what it is. You can't change it, so there's no point in thinking about it too much."