2011 will be the first season in four decades in which no fewer than five world champions line up on the grid.

Among new champion Sebastian Vettel's rivals next season will be former title winners Jenson Button (2009), Lewis Hamilton (2008), Fernando Alonso (2005-6) and Michael Schumacher (1994-5 and 2000-4).

The only previous occasion on which the F1 grid boasted five active world champions was 1970, when Jack Brabham, John Surtees, Denny Hulme, Graham Hill and Jackie Stewart were all racing.

And that season's ultimately posthumous world champion Jochen Rindt was killed at Monza in September.

There have never been six active world champions all still driving in F1 at the same time.

But if 2007 world champion Kimi Raikkonen had returned to F1 from rallying, and Jacques Villeneuve had successfully formed his own team in collaboration with Durango, there might be no fewer than 7 world champions on the 2011 grid.

On a 24 car grid, that would represent almost 30 per cent of the entire field.