McLaren on Thursday announced that Danish novice Kevin Magnussen will be Jenson Button's teammate for the 2014 season.
Magnussen, 21, is the son of former Formula One driver Jan and won this year's Formula Renault 3.5 feeder series.
He replaces Mexican Sergio Perez, who announced his departure on Wednesday after just a year with the team.
"We're delighted that Kevin will be joining Jenson for 2014," said team principal Martin Whitmarsh.
"Their confirmation is an important step for us as we continue to strengthen our organisation ahead of the 2014 season.
"Kevin is clearly very talented and very determined, and we therefore have high hopes for him."
McLaren are without a win or even a podium position this year and are heading towards their worst season in modern times going into the United States Grand Prix this weekend.