Jacques Villeneuve says Lewis Hamilton "fell asleep" in response to the easy challenge from his new team-mate Valtteri Bottas before Sebastian Vettel "woke" him up.
Vettel was the driver in form at the start of this season, winning three of the first six races to hold a 25-point lead over Hamilton in the wake of the Monaco Grand Prix.
But while it initially appeared as if this could be Vettel's season, Hamilton came to the fore in the second half of the campaign.
The Brit won five of the seven races since the summer break to wrap up the Drivers' Championship in Mexico with two races to spare.
"Lewis is really, really good," Villeneuve told Autosport.
"He's only ever been in the best team with the best car, or close to it, like every great champion, which is fine.
"If he can be the whole season like he's been since the summer break, great, but he hasn't done a full season like that.
"He wasn't there. I think he fell asleep with Bottas, and when he realised that Bottas wasn't the one he had to fight, it was actually Vettel, that's when he woke up.
"He spent years with Nico, and it was always tough with Nico.
"Then when Bottas arrived he was laughing – 'phew, finally I'll have an easy championship.'
"After a while, he realised, 'crap, Ferrari is there and Vettel is there.' And Vettel is not one to give up."
All in all the 1996 World Champion believes this has been a good season for Formula 1.
"It's always good when Ferrari is in the mix, and it's always good when it's a battle.
"On that aspect, it's been a good year to have faster cars, and it's been a good year because we've been used to terrible years!
"So right now we're saying, 'Wow this was an amazing year.'"
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