McLaren announced on Monday that Tim Goss has been appointed as the British team's new technical director and will replace Mercedes-bound Paddy Lowe at the end of the year.
Mercedes are still to confirm Lowe's arrival, but McLaren team principal Martin Whitmarsh thanked him for his work with the team.
"Paddy has been a good and successful technical director and we wish him well when he embarks on a fresh challenge in 2014," he said.
Formerly McLaren's director of engineering, Goss joined the team in 2000 and has contributed to five drivers' championship successes and three constructors' world titles.
"His quiet and unassuming persona conceals a fierce competitiveness and a wealth of experience, coupled to an unrivalled level of expertise in the field of Formula One car design and engineering," said Whitmarsh.
Lowe's departure seems certain to create speculation about the role of Mercedes team principal Ross Brawn, who has had to defend his position in recent weeks after Toto Wolff was appointed head of motorsport.
Whitmarsh said that Lowe "will be performing a different role" during the final year of his contract with McLaren, without providing further details.
He added: "I firmly believe our technical and engineering team is the best in the F1 business and that its strength in depth has always been, and will continue to be, an important element of our on-track success.
"Moreover, I'm certain that, in his expanded role, Tim will continue to lead it very capably and will evolve and improve it.
"That's his brief and it's already clear he's prepared to embrace it with energy and enthusiasm."