Lewis Hamilton had endured one of the toughest weeks of his career in the run-up to Britain’s biggest motor race, having found himself at the centre of a storm of criticism over his celebrity lifestyle. But a few words before the race from Nic, Hamilton’s brother, who suffers from cerebral palsy, reminded him that he had the talent, if he could deliver the commitment.

Hamilton said: “My brother came into my room just before the race and he just told me, ‘You are the master in the wet. Don’t worry.’ ” It was enough to propel him to victory in his home grand prix, one of the greatest in the history of Silverstone.

In spite of his frequent media exposure with supermodels and at parties around the world, Hamilton’s family remains his anchor. They were all there to watch his win: Anthony, his father and manager; Linda, his stepmother; Carmen, his mother; Nic, and even his grandfather, Davidson, who flew from his home in Grenada.

And then there were the 90,000 fans, desperate for the first British winner of the race since David Coulthard in 2000. Hamilton had heard from them direct, stopping on his way into Silverstone for autographs and a chat.

“When I woke up, I wasn’t feeling great, but when I got to the track, I met some fans and they gave me so much energy,” he said. “It has been a tough time personally. I have had a lot of difficult emotions to cope with . . . I just wanted to wipe the slate clean.”

With the race moving to Donington Park in 2010, Hamilton had only two chances to add his name to the list of British drivers who have won on this track, but needed only one.

It certainly seemed that the rain that drenched Silverstone yesterday was a sign from above that the historic circuit’s time is up. Bernie Ecclestone, Formula One’s commercial rights-holder, confirmed that even if Donington’s reconstruction programme fails to meet his deadlines, the race will not return to the Northamptonshire track.

“We won’t come back,” Ecclestone said. “I am sure they will be ready but, if not, we will sign with another country. There won’t be a British Grand Prix. Pure and simple.”

There is widespread scepticism that Donington can be ready within two years and confusion surrounds the £100 million redevelopment plan. Ecclestone had spoken at length about an English businessman he had met who was behind the plans.

Simon Gillett, Donington’s joint chief executive, pulled back yesterday from a statement that spoke of a “private investor”, insisting that the plans will be self-financing, using the sort of debenture scheme that helps to finance Wembley and Wimbledon. “We have a lot of exciting plans and there will be more coming out in the next few days and weeks,” he said.

But such a scheme is unlikely to raise the entire £100 million, with about £30 million needed to improve the inside of the circuit and a further £70 million for perimeter development, which will include hotels and a shopping mall.