Lando Norris has refuted Max Verstappen's claim he would've won the title "even earlier" in the McLaren, insisting Red Bull's early-season lead was insurmountable.
Verstappen and Red Bull picked up where they left off last year with an emphatic 22-second victory at this year's season-opening Bahrain Grand Prix where he led home a Red Bull 1-2.
Third-placed Carlos Sainz was 25s down on the Dutchman while Norris, the best-placed McLaren driver in sixth place, was 48 seconds off the pace.
Verstappen went on to win four of the first five races, putting him 52 points ahead of Norris before the Briton secured his debut victory in a heavily-revised McLaren at the Miami Grand Prix.
But as the reigning World Champion continued to eke out wins and podiums, doing so even as Norris' McLaren emerged as the car to beat and Red Bull suffered major balance issues, his advantage grew to 84 points after the British Grand Prix before Norris pulled it back to 44 in the Brazilian Sprint.
Norris' campaign imploded a day later as Verstappen won the Grand Prix, the gap back out to 62 points, before he extended that to an unbeatable 63 in Las Vegas to wrap up the World title.
A bullish Verstappen insisted to the media that he was proud to have won the title in a car that was not the fastest for much of the season.
"I'm also very proud of this season because for most of the season, I would say for 70 per cent of the season, we didn't have the fastest car, but actually we still extended our lead," he said. "So that is definitely something that I'm very proud of."
He believes if he'd been racing Norris' McLaren MCL39, he would've won the title "even earlier, so [I would have been] further ahead".
Norris, however, doesn't agree as he believes Red Bull's early-season advantage was too big to overcome once McLaren found their rhythm.
Asked if Verstappen could've won in the McLaren, the three-time Grand Prix winner told The Telegraph: "No, definitely not.
"I mean, no one ever in the history of Formula 1 has come back from the size of deficit I had. No one. Ever.
"And there have been much bigger swings of performance of cars in the past than there has been now.
"The advantage they [Red Bull] had in the beginning of the season over everyone was way more than we've had.
"I think if it was any other driver, well not any other driver but if it wasn't Max and Red Bull, I think the chances [of winning the title] would have been much higher."
McLaren can still win the Constructors' Championship for the first time in 26 years as they sit 24 points ahead of Ferrari with two races remaining.