Damon Hill has raised questions over Lewis Hamilton's future in F1 ahead of the Briton's 17th season in the sport.
The seven-time World Champion's current contract with Mercedes is set to expire at the end of 2023, though he has previously voiced his intentions of signing a new multi-year deal with the team.
Despite this, Hill believes that Hamilton may soon have to consider what is keeping him in Formula 1.
"How does a driver know when it’s time to go?" Hill wrote for The Telegraph.
"If this is not a question Lewis Hamilton is pondering very hard at the moment, as he prepares to begin his 17th season in Formula 1, it is certainly one he’s going to be asked at an uncomfortably increasing rate as the clock ticks down on his stellar career.
"As far as we know, he has no contract for 2024. The game of 'guess what number I'm thinking of' will be being played between him and Toto Wolff as the races count down this season.
"If he wins that fiendishly elusive eighth world title, will he plant his flag on the summit of F1 record books and call it a day? Or if he doesn't win, will he press on in hope, vain or otherwise?"
Hill reflects on Hamilton's motivation
Hill – who left F1 in 1999 at the age of 39 – admits that deciding when to retire can be a difficult decision for a driver. However, he believes that Hamilton has the ability to continue into his 40s if he wishes, much like Fernando Alonso.
"It's not always easy to get it right," Hill said.
"At 38, Lewis is obviously getting on in terms of years, but he remains as quick as ever. And as fit.
"With the way the drivers look after themselves these days, and power steering in the cars, I don't believe there is any physical reason he could not carry on driving well into his 40s if he was motivated to do so. Fernando Alonso is living proof of that.
"The question is, what is keeping him here? Is it just about getting that eighth title? Will he retire if he does it? Or is it because he wants to keep racing for the love of it?
"Personally I can't see Lewis driving around in circles trying to pick off podium places, as Fernando has been forced to resign himself to."
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Hill: Hamilton's next move will be fascinating
With Hamilton yet to sign a new contract, Hill is curious about the reasons behind this.
"While both he and Mercedes have been saying for months that he plans to carry on, the fact remains that with less than a week until the first race of the year on March 5, nothing has yet been announced. It begs the question, why?" the former F1 driver continued.
"One possible explanation is that both sides are waiting to see just how competitive Mercedes are before committing to a new deal.
"If they start 2023 miles off the pace, perhaps Lewis
will be less minded to sign a new long-term deal? Or perhaps it is the
team who are dragging their heels?
"Lewis does not come cheap. He gives Mercedes a lot but he costs them a lot too. In George Russell they have a young driver who might be capable of delivering a title in the right car.
"I don't think anyone outside of Lewis and Mercedes know the answers to these questions but one thing we do know is it’s a critical moment in the career of one of the sport's all-time greats."
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