Helmut Marko believes that Lewis Hamilton will not be able to retain his current level of performance for much longer.
The seven-time World Champion fought closely for the title with Max Verstappen throughout the 2021 campaign, and just missed out on an eighth championship in the controversial final laps of the Abu Dhabi Grand Prix.
Red Bull advisor Marko was impressed by what Hamilton achieved in the season, particularly in the latter half where he won several races.
"He worked a great second half of the season," Marko told Austrian newspaper OE24.
"Hamilton's age will come into play"
However, with Hamilton having recently turned 37, Marko thinks that the Briton's age will eventually start to have an impact on his ability behind the wheel.
"I can't imagine that he can continue to drive at this high level for much longer," Marko said.
"He has reached his peak level now, but at some point his age will come into play."
The Red Bull man takes the opposite view of Verstappen. After winning his first World Championship, the Dutchman will continue to improve as a driver, according to Marko.
"Max is a World Champion now and will only get stronger," Marko added.
Hamilton feels at his best
Despite Marko's comments, Hamilton spoke during the recent pre-season test in Barcelona of how he continues to feel at his best.
There was much speculation over the winter break about whether the Mercedes driver would return to F1 in 2022 following the events of the Abu Dhabi Grand Prix, but Hamilton says that he still loves his job too much to walk away.
"I did make a commitment to the team earlier on in the season," he explained to media including RacingNews365.com, referring to the contract he signed in 2021 that will keep him at the Silver Arrows until the end of 2023.
"And ultimately, I love what I do. I love being a part of a team. I love working with - and I've said it so many times - everyone towards a common goal. And I feel at my best, so why do I need to leave?
"Of course, dealing with... There are so many different ways you can refocus and get recentred, and I would say this one was one of the best that I've experienced."
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