Sebastian Vettel admits that he never developed any off-track "chemistry" with Fernando Alonso in the way that he did with the likes of Lewis Hamilton.
The four-time World Champion enjoyed many on-track battles with Alonso during his F1 career, as well as going head-to-head with the Spaniard for the title in 2010 and 2012.
Vettel – who retired from the sport at the end of the 2022 campaign – still has fond memories of their championships showdowns.
"I think I admire him as a competitor," Vettel told the Beyond The Grid podcast.
"He's probably been the toughest one, especially in [those] first couple of years, and we had [such] close battles at the end of the championships, both in 2010 and then 2012, in particular, which is still probably one of my favorite moments/memories.
"Just the tension coming into the 2012 Brazilian Grand Prix, that morning, that build-up.
"I think that, for me, at least – I don't know for the people who were there, [they] were probably more relaxed – but for me, it was very intense, and I think both of us were very nervous."
Vettel: I don't really know Alonso
While Vettel respects Alonso as a rival, he feels that he never really got to know him well away from the circuit.
"I rate Fernando really high as a driver," the German said.
"I think he has got so much natural talent, incredible determination, great racing instinct, and all of that he hasn't lost. You can see he loves his racing. He's very passionate.
"As a person, though, I don't know him, really. I wouldn't say we don't get along, I think we respect each other. But it's just never happened that we really got to know each other, spend time [together] or talk much outside racing."
Vettel has spoken of how his clash with Hamilton at the 2017 Azerbaijan Grand Prix enhanced his relationship with the Briton, but he admits that there was never a moment like this with Alonso.
"Maybe we didn't have that moment, like I had with Lewis, that brought us together," Vettel continued.
"I think he's a great competitor, probably one of the most difficult I've ever had, because he's just always there and never backs off, but also very respectful when it comes to wheel-to-wheel racing, [which] I've enjoyed so much.
"But, as a person, we probably don't have the best of relationships, because we just don't know each other so well."
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Alonso and Vettel 'two very different people'
Vettel thinks that, despite having a shared passion for racing, he and Alonso are different characters.
"Maybe we are too different," the former Aston Martin driver commented.
"We have racing as a common passion that excites us both, but then it just never happened that we, in all these years, really got to know each other.
"It's probably like in school or at work, you have a colleague that you respect but you don't really know.
"As much as I get on with Lewis and we have stuff to talk about and maybe some views that we share, with Fernando I might have these as well but we just never had the chemistry to really get into this.
"So I think, despite having the same big passion in our lives, we're probably two very different people."
In recent years, 35-year-old Vettel and Alonso, 41, have been two of the older drivers in the field.
"I think we are maybe now, in terms of age, getting closer," Vettel said.
"The gap's always been the same but, obviously, you could argue I'm closer to him than maybe to somebody who's coming in [at] 20 today.
"Bu [we are] probably just two different people and we are probably in a very different point in our lives, despite the fact that we've been racing each other for so long."
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