Lewis Hamilton was today told to keep trusting his father and ignore criticism of the way his Formula One career is being managed. John Surtees, the senior statesman of British motor racing, spoke out as Hamilton added Reebok to a lucrative portfolio of sponsors signed by father Anthony.

Just three days before the start of practice for the British Grand Prix at Silverstone, 23-year-old Hamilton was busy in Amsterdam being unveiled as Reebok's new sporting ambassador in a deal reported to be worth up to £ 10million over three years.

Since failing to score in last week's French Grand Prix, where he was penalised for cutting a chicane, Britain's star driver has spent two nights in London helping to celebrate Nelson Mandela's 90th birthday along with stunning Pussycat Doll Nicole Scherzinger, crewed a yacht belonging to backer Hugo Boss off the Isle of Wight, demonstrated a McLaren racing car at the Brooklands Festival and then turned up in Holland.

Hamilton's hectic celebrity lifestyle has led some observers to voice concern the 23-yearold, in only his second season among the F1 elite, is no longer fully focused on his driving.

That, they contend, is the reason why Hamilton goes into the ninth round of the world championship trailing the Ferrari of Brazil's Felipe Massa by 10 points.

Surtees (right), the 74-year-old who remains the only man to have won world titles on motorbikes and in F1, rejected the argument even though Hamilton has also made errors in Canada and Bahrain.

He said: "We've got to remember that since Lewis started racing at the age of eight, father and son have been under pressures of one sort or another.

"Pressure is nothing new to them. They are racing people and have been at it for many years. The only difference now is that the pressures are relative to the demands being made by sponsors wanting to maximise their return.

"Yes, the financial rewards that come from all this can be a temptation and can be a diversion. But I've spoken to Anthony in the past and I'm confident he can ensure Lewis prepares himself properly for Sunday's race.

"Things haven't gone exactly right in his last Grands Prix but the fact remains that he and McLaren can get it together. They will be up against very formidable opposition at Silverstone.

"With all respect to McLaren, I think Ferrari are more together as a team."

Surtees, who is promoting a new model Scalextric Silverstone set, went on: "I like the way the Ferrari has been performing. [Kimi] Raikkonen and Massa don't look like they're having to work as hard as the McLaren lads. At the same time,

McLaren have a wealth of experience and in Lewis they have also an extremely good driver, one who can get the job done. And I believe he can do that on Sunday."