In what represents a coup for the Woking team, the highly-rated Key is set to spearhead a new-look technical operation as they continue to make changes in a bid to move back up the grid after four years without a podium.
A McLaren spokesman said Key would be joining them, but no other details have yet been released.
The signing follows an overhaul of McLaren’s leadership structure at the start of July, which followed the departure of Eric Boullier.
Zak Brown, the team’s executive director, said the reason’s for the team’s underperformance were “systemic and structural” and required “major change from within”. He also promised that more appointments were afoot.
Englishman Key is regarded as one of F1’s foremost technical minds and has worked at Toro Rosso, Red Bull’s junior team, for the last six years. The 46-year-old has been linked with various moves to bigger-name rivals over recent seasons, but previously expressed his happiness at Toro Rosso.
Toro Rosso are yet to comment.
Key’s F1 career began in 1998 at Jordan and he moved up the ranks at the team over the following decade as they ultimately morphed into Force India, before spending a short stint at Sauber in 2010-12.
McLaren’s winter switch from Honda to Renault engines has yet to result in an anticipated big move back up the field for the former world champions, with the team slipping to seventh in the Constructors’ Championship in recent races.
McLaren’s overhaul in focus
It has been a year of change at McLaren.
In April, Tim Goss left his position as chief technical officer as it became transparent that the team had fallen short with their 2018 car, the MCL33.
Separately, executive director Zak Brown was put in formal charge of the team’s F1 operations by being given the title of CEO of McLaren Racing.
Last month, the team announced that racing director Boullier had resigned as the team embarked on a management reshuffle to fix “systemic and structural” flaws.
Gil de Ferran was appointed sporting director while Andrea Stella, who joined McLaren from Ferrari alongside Fernando Alonso, became performance director, and Simon Roberts promoted to chief operating officer.
Amid speculation that Matt Morris, chief engineering officer, is to leave the team, the highly-rated Peter Prodromou remains in place as head of aero.
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