Mika Hakkinen reckons Lewis Hamilton continuing in Formula 1 could be dependent on how competitive the 2022 Mercedes W13 turns out to be.
With Hamilton maintaining radio silence in the wake of the dramatic 2021 title decider, speculation is rife the seven-time World Champion could call time on his career as F1 ushers in a new technical rules era.
Hakkinen, who walked away from F1 in 2001 while still at the top of the sport, says Hamilton is likely weighing up all his options over the course of this winter.
"Lewis' journey in Formula 1 has been really long and there are so many elements which will come into his opinion as to whether to continue," Hakkinen told the Press Association.
"Lewis has the confidence. He has been winning, he has been on the top of the podium and everybody has been looking at him like, 'Wow, you are great'.
"He is thinking that it must continue this way, so this is going to be a very interesting year for him."
F1 changes could be "really hard" for Hamilton to accept
The new ruleset for 2022 means it is entirely possible Mercedes no longer find themselves at the top of the sport, which could resign Hamilton to fighting for positions far lower than he has grown accustomed to.
Should this happen in the first year of the new regulations, Hakkinen thinks Hamilton will struggle to accept the circumstances.
"The regulations in Formula 1 have dramatically changed," he said.
"It is going to be a completely new machine and the chances are that the designers might not find an optimum machine. If that happens to Lewis, it is going to be really hard for him to accept.
"If you have been at the top of the mountain and suddenly you have to climb back up the mountain because you don't have the best car, it is going to be emotional for him to control.
"There are a lot of question marks surrounding Lewis. We don't know whether he is coming back, but let's hope he is."
Hakkinen is set to take part in this weekend's Race of Champions in Sweden, where he will partner Valtteri Bottas for Team Finland in the Nations Cup on Saturday before gunning for individual glory on Sunday.
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