Ron Dennis, McLaren's embattled team principal, will come out fighting for a new Formula One season in defiance of rumours that he is on the verge of quitting. Dennis has refused to be drawn into the public debate over his future, which was stoked when British and Italian detectives raided his house this week in a new stage of the “Spygate” affair.

But The Times can reveal that Dennis will not be hounded out of the team he has led for the past 28 years, nor will he miss the first grand prix of the 2008 season, in Australia. His destiny is in his own hands and he will decide what his future role with the team will be when he is ready. One theory is that he may step back from the front line of Formula One as team principal but he would, even then, remain in overall control and still attend races.

A source close to Dennis said last night: “There has been a lot of talk of Ron missing the race in Melbourne and then resigning from McLaren. He will be in Melbourne [on March 16], but may be late due to a number of other commitments. But there is no question of him being under pressure from anybody to throw in the towel. He sees this season as a big opportunity to put McLaren back on track and repair some of the damage of last season. He is as determined and focused as ever.”

Dennis endured the most gruelling year of his life when it was revealed that a 780-page dossier of secrets belonging to Ferrari had been passed to Mike Coughlan, McLaren's chief designer. Coughlan was suspended but the reverberations ripped through the sport throughout the second half of last year. A series of inquiries by the FIA, the governing body, resulted in a world-record £50million fine being imposed on the team, while McLaren were disqualified from the constructors' championship, a title the team would have won easily from Ferrari.

But the drama has not ended there and the co-ordinated raid on the home of McLaren executives this week is thought to have produced evidence that some senior managers at McLaren's headquarters in Woking, Surrey, may have had knowledge of Ferrari secrets. If proved, that could lead to serious consequences for senior staff and deal a further blow to McLaren's prestige.

Dennis is defiant and confident in his personal integrity. There is no doubt that he has been under enormous pressure as his team have staggered from one calamity to another. But Vodafone, his title sponsor, and Mercedes, the chief shareholder in McLaren as well as the team's engine supplier, have not wavered in their support, in spite of the almost constant barrage of speculation about his future. That means Dennis is free to decide his own future as chairman of the McLaren Group and a key shareholder in the business that he created over three decades.

One key reason why he will not walk out is that he wants to leave Formula One at the top. Lewis Hamilton, the prodigy he groomed for a decade, was within touching distance of becoming the most astonishing world champion in history in his maiden season last year, failing only at the final race. Dennis believes the new McLaren car for 2008 is a winner and a title for Hamilton would be the perfect antidote to the poison that has afflicted his life in the past few months.

Hamilton confirmed as much yesterday when he declared his MP4-23 car to be in good shape for Melbourne. After three final days of testing in Barcelona, Hamilton believes that his car will measure up to the stern competition from Ferrari and Kimi Raikkonen, the man who beat him to the championship last year.

“Winter testing has gone really smoothly,” Hamilton said. “We have had steady reliability and the car is feeling good. We have had some great testing days, easily covering the mileage and getting confidence in the car.”