McLaren have confirmed signing Sergio Perez on a multi-year deal from next season as a replacement for Lewis Hamilton, who is on his way to Mercedes.
The Woking-based marque have trumped an announcement from Mercedes regarding Hamilton's switch with a statement regarding the 22-year-old Mexican.
Perez said: "I'm thrilled and delighted to have become a McLaren driver."
Perez, currently with Sauber and a product of Ferrari's young driver academy, had been linked with a move to Maranello as replacement for Felipe Massa.
However, Ferrari president Luca di Montezemolo scotched that move by claiming Perez lacked the necessary experience, despite finishing on the podium on three occasions this season, most recently in Italy behind Hamilton.
Although McLaren team principal Martin Whitmarsh claimed at Monza there was "no plan B" in the eventuality of Hamilton leaving, it is now clear the team have worked quickly to bring in Perez.
Perez added: "The McLaren name is one of the greatest in the history of Formula One. For more than 40 years McLaren has been a team every racing driver has aspired to drive for.
"I was brought up on the great stories of Ayrton Senna's many world championship triumphs for McLaren, and I'm truly honoured they've chosen me to partner Jenson (Button) from 2013 onwards."
With Mercedes set to confirm Hamilton's appointment at 10am, Whitmarsh paid tribute to the 27-year-old for the role he has played over the last few years.
Whitmarsh said: "It's entirely appropriate I should take this opportunity to pass on our thanks to Lewis. He wrote a huge chapter of his life and career with us, and was, and always will be, a fine member of an exclusive club - the McLaren world champions' club.
"It goes without saying we all wish him well for the future, just as it also goes without saying we hope and believe Sergio, too, will become a member of that exclusive club before too long."