Christian Horner feels that Lewis Hamilton has never "recognised" the ability of 2021 Formula 1 title rival Max Verstappen.
The two drivers were embroiled in of the championship's finest ever title battles in 2021, with multiple flashpoints along the way, including collisions in Britain, Italy and Saudi Arabia.
The title itself was decided after they went level on points into the Abu Dhabi finale - where the fumbling of Safety Car restart rules by race director Michael Masi.
While Mercedes and Hamilton eventually rescinded their appeal and accepted the result, Horner does not believe the seven-time World Champion has respected Verstappen's abilities.
Hamilton has not "recognised" Verstappen - Horner
"There's a difference, perhaps a different respect," Horner explained to the F1: Beyond the Grid podcast when asked if Verstappen races Hamilton differently compared to 2022 rival Charles Leclerc.
"With Charles, they've raced each other since they were kids, and there was a mutual respect.
"I've never once ever heard Lewis recognise Max's ability, and so of course, there was just a bit more needle. You could feel that and you could sense that between those two drivers.
"You can't not respect everything that Lewis has done and achieved. It is remarkable and probably never to be bettered, but everybody is beatable at some point in time.
"Max had a respectfulness, but he wasn't in awe of him or he wasn't afraid of him, and he relished going up against him, relished the opportunity to go wheel to wheel Racing with him.
"Ultimately, he believed that he could beat him. And it was that inner belief and self confidence that on so many occasions came through.
Horner also believes that Hamilton was rattled by Verstappen in 2021 - especially as the latter "had nothing to lose."
"He's the seven-time world champion that has everything to lose, Max is the young kid that's taking the risks, that's throwing everything at it, and got nothing to lose - some of his overtaking last year was was stunning," he added.
"And I felt that started to rattle Lewis.
"Definitely after Lewis qualified on pole at Silverstone, and Max won the sprint race you saw Lewis was a bit broken after. Had Max made it through Copse, I don't think, they'd have seen him again that afternoon.
"So as an air of desperation building in, it was high stakes stuff and your emotions run high, but it probably affected Lewis arguably more than Max because, as I say he'd got more to lose than Max."
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Verstappen more polished now
Horner also added that he felt the 2022 Verstappen was "more polished" - but would have have dealt with the flashpoints in '21 any differently.
"The Max we have now is just a slightly more polished version, but he's an attacking driver," said Horner.
"He's convinced at Silverstone he left enough enough room. I think that we put him in the situation in Monza where he had a slow pitstop and we should have never been anywhere near Lewis.
"But again, he felt that there was enough room in the move that he that he made.
"When you look at the advantage that Lewis had in Brazil, the only car couldn't pass for 30 odd laps was Max.
"Every other car, it took him a lap, a lap and a half to pass.
"For me, it was a titanic drive by Max - he's fighting for a world championship. He's the type of driver that gives it absolutely everything. And it was was hard racing, but it was fair racing.
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