Red Bull team boss Chris Horner believes that any of the drivers in the top six can win the world championship this year.
Ferrari's Fernando Alonso has led the championship for most of the season but Sebastian Vettel's victory at the Singapore Grand Prix has cut the lead to just 29 points.
Kimi Raikkonen, Lewis Hamilton, Mark Webber and Jenson Button complete the top six, and Horner is adamant that any one of those drivers could claim the title this season.
"The championship is wide open. It's just annoying Fernando keeps popping up on the podium at the end of the grand prix," said Horner. "You have to include Mark, you have to include Jenson, even Kimi isn't far off and of course Lewis. There's six races still to go - 150 points still available, still a lot to play for.
"Sebastian was 25 points down with two races to go in 2010, which indicates anything is possible for all the drivers.
"We need to keep taking points off Fernando, which ideally means getting a few more cars between us and him."
The next race is the Japanese Grand Prix on October 7.
