Christian Horner says McLaren is now a weaker team after the loss of Lewis Hamilton to Mercedes for the 2013 F1 season.
Hamilton revealed earlier this year that his 14-year relationship with McLaren was to draw to a close at the end of 2012, with the Briton inking a deal to partner Nico Rosberg in the Mercedes line-up from next season onwards.
McLaren will replace Hamilton with Sergio Perez after the Mexican impressed this season with three podium finishes for Sauber, although the youngster also suffered his fair share of issues on track and failed to score following the announcement of his move.
Recent seasons have seen McLaren – with a partnership of Hamilton and Jenson Button – as one of the main challengers to Red Bull in the title race, and Horner admitted that losing the 2008 champion would be a blow for the Woking-based outfit.
"I think McLaren is a weaker team without Lewis," he was quoted by the Press Association
. "I think McLaren would admit that. Lewis is an outstanding driver and in Lewis and Jenson they had a hugely strong driver line-up.
"Whichever team had taken Lewis, he would be an asset. I'm sure he will naturally add performance to Mercedes next year."
However, Horner added that only a fool would write off McLaren in the title race given the success the team has enjoyed in the past.
“McLaren have had a great car this year,” he said, “and who's to say they won't have an even better one next year?”