Nico Rosberg insists he respects Lewis Hamilton but he is far from friends with his Mercedes team-mate and Formula One championship challenger.
The two Mercedes drivers are locked in a fierce battle for the drivers' championship, with Rosberg holding just a one-point lead over Hamilton.
Rosberg started the season with four wins from the first four races but has won just once in the last six, seeing Hamilton close the gap.
The pair have collided twice in 2016, with their already rocky relationship reaching new levels of tension -Mercedes handing them a final warning for their behaviour on track.
And Rosberg has opened up on his relationship with three-time F1 champion Hamilton ahead of the weekend's Hungarian Grand Prix.
"Beating Lewis...he's one of the sweetest opponents," the German told the Guardian.
"He's one of those opponents where you get the greatest satisfaction from beating him because he's world champion.
"I have huge respect for him but, well, we're not best friends at the moment. That's the difficulty between us now. We're just both so competitive and that makes it difficult to be friends because the competition is so extreme.
"It was the same back then. How many pizzas could we eat? Who could run fastest from the lift to the hotel room? It would be competition all the way but there was not the surrounding influence with a team, the media and money. That makes it difficult now.
"I do recognise his achievements. He's done some great things and he's been beating me. I have to fight back and that's the awesome challenge."
Rosberg says he hopes Hamilton's "wave" of good form is coming to an end, with the Briton having won four of the past five races.
"If I focused on points and championships I'd be massively disappointed because I was 40-whatever points ahead and now it's one, but I'm not focusing on it," Rosberg said.
"Momentum does play a role. We've seen it with Lewis and I from 2014. We've always gone in waves. It's strange but it must be time for his wave to be ending now.
"But, yeah, it's difficult to have a race like Silverstone. Second place - I could have lived with that but to lose points and finish third? That's tough."