Martin Whitmarsh has warned Lewis Hamilton that he is making "a mistake" by walking out on his lifelong team, McLaren, to link up with rivals Mercedes.
The 2008 world champion on Friday ended weeks of frenzied speculation by confirming his imminent defection from Woking to Brackley, on a three-year deal worth up to $100 million.
Whitmarsh, the McLaren team principal, is adamant that Hamilton, who has been on the British team's books since the age of 13, will live to regret his choice. "Mercedes-Benz is a great partner of ours and they are a great team," he said. "But anyone leaving McLaren, who wants to win, I think that's a mistake because I have faith and belief in this team.
"Whether you measure it over the last four races, four years or 40 years, we're a fantastic team. I wouldn't advise anyone to leave McLaren if they want to win. But I've got to respect Lewis's decision and really wish him well."
Hamilton's announcement was the culmination of one of the most drawn-out transfer sagas in recent Formula One history. But it was not even the first transfer announced yesterday. McLaren pre-empted Mercedes' big announcement with one of their own, unveiling Sauber's Sergio Perez as Hamilton's replacement.
Trying desperately to put a positive spin on Hamilton's departure, McLaren claimed that in the 22-year-old Mexican and Jenson Button they now had the "perfect blend of youth and experience". It may be an exciting line-up, and Perez may be rich in potential, but even Whitmarsh did not deny later that Hamilton had been their No1 choice.
"I know we made a very, very big financial offer, bigger than I believe any Formula One driver is enjoying today," he said. "We went a long way to make a good offer to Lewis but ultimately it takes two to get to a signature. We clearly didn't agree terms and we've moved in a different direction."
The question now is whether heads will roll at McLaren for failing to get Hamilton to sign. It would seem doubtful although executive chairman Ron Dennis was clear at Monza three weeks ago that it was Whitmarsh's responsibility to get Hamilton over the line. He failed to achieve that.
Asked about Dennis's reaction to that failure and whether he might contemplate retiring as a result of having let one of the fastest drivers of his generation slip through his fingers, Whitmarsh chose to avoid the question.
"Ron is a racer," he said. "He understood. What is important is actually what we are doing with the team and he knows, as we have monitored Sergio over a number of years, that he is a massively exciting talent and we have the opportunity now to mould him and we like doing that. We are looking forward to completing this season successfully and also to next year."
Whitmarsh, who said that Hamilton had broken the news to him on Wednesday in an "emotional" phone call from Asia, where he stayed after last weekend's Singapore Grand Prix, instead tried to focus on Perez and what he could bring to the team. There has been plenty of speculation that McLaren's title sponsors, Vodafone, may be about to pull out and that what Perez might bring to the team is lots of much-needed cash via his backers Telmex, but Whitmarsh denied that had been a motivating factor. McLaren are understood to be paying Perez about pounds 7?million per season, and Whitmarsh says there are no "side deals".
"I did have a conversation with [Telmex board member] Carlos Slim yesterday but we have made an offer to Sergio, we are paying him well and there are no side deals," he said. "I'm not saying that ultimately there won't be other fresh partners coming forward because of it but that wasn't the motivating force."
Whitmarsh added that other drivers, such as Force India's Paul di Resta, had been in the frame but ultimately fell down because McLaren had already been down the all-British route and it would be hard to top the Hamilton-Button partnership. "The true answer is that I rate Paul but it would probably have been continuing a little bit too much with the British theme to have gone that route," he said. Hamilton said his decision to quit his boyhood team had been motivated by the desire for a "fresh challenge".
McLaren have won 16 times and finished on the podium four times in the period since Mercedes returned as a full works team in 2010. But despite his new team having won just once, with six podiums, in the same period Hamilton said he was confident he could help begin a "new chapter" for the famous Silver Arrows. "Together, we can grow and rise to this new challenge."
Mercedes team principal Ross Brawn claimed that despite speculation to the contrary his team had not offered more money than McLaren. "Lewis didn't come here because we offered more money, because we didn't," he said. "I think for Lewis, the attraction was being part of that building structure - the creation of the team. Not walking into a ready-formed, successful package; it was being part of the process of building that package."