Decision time for Red Bull

Vettel's championship hopes are less, but team must decide whether to back Webber or maintain an even hand, risking both drivers taking points off each other.

The Formula One team with the most to gain also has the most to lose: that is the dilemma facing Red Bull-Renault as the world championship gears up for a two-pronged showdown in Brazil and Abu Dhabi.

Unlike immediate rivals Ferrari and McLaren-Mercedes, Red Bull have never won an F1 title.

Created from the remains of the failed, Ford-owned Jaguar team, Red Bull made their grand prix debut in 2005, scored their maiden victory four years later and have emerged this season as a fully fledged championship contender with the fastest car on the grid.

Their problem? Time is running out and Red Bull lost ground during last weekend's Korean Grand Prix, where Mark Webber crashed out of second place and Sebastian Vettel suffered an engine failure, gifting the race - and the championship lead - to Fernando Alonso, the Ferrari driver.

Webber trails by 11 points and Vettel is 25 adrift, so the team have to decide whether to allow both drivers to race openly - and risk taking points off each other, to their rivals' profit - or ask Vettel to play a supporting role, sacrificing his own title ambitions to maximise those of his teammate.

If Webber wins both remaining races he will be champion, regardless of what Alonso does, while Vettel is going to need his Ferrari rival to score no more than 24 points in the two races if he is to be the first German champion since Michael Schumacher.

So there is a serious danger of the team missing out on the drivers' title, although they are looking strong for their first constructors' crown, leading McLaren by 27 points and Ferrari by 52.

In public, the team insist they will maintain an even hand. In an interview published on their website earlier this week, Christian Horner, the team's sporting director said: "We have two fantastic drivers and will continue to support them equally, in line with our ethos."

Officially, of course, team orders are banned. There is tacit acknowledgement, however, that they are acceptable during a championship run-in - as was seen in 2007, when Felipe Massa backed off during the Brazilian finale to enable Kimi Raikkonen, his then-Ferrari teammate, to go past him so the Finn could take both race and title. The situation is more clear-cut for Red Bull's adversaries. Ferrari has only Alonso in the hunt and Lewis Hamilton is the lone McLaren driver whose prospects appear realistic.

Jenson Button retains a chance of a successful title defence, but that will evaporate if Alonso finishes sixth or higher in Brazil.

Horner believes that there might yet be more twists and turns in this most extraordinary of seasons, in which the championship lead has been traded five ways - Vettel is the only driver from the top three teams not to have headed the standings outright.

After the race in Korea, he said: "The championship situation effectively changed hands three times today - and in quick succession, Mark remains second in the points table and Sebastian has dropped to fourth, but they are still within one win of Alonso.

"How many times have we seen the championship lead switch to and fro this year? It's impossible to have a crystal ball and predict what will happen in the final two races, but I genuinely believe this championship will go down to the final lap in Abu Dhabi."