Berlin - Just three races into the Formula One season, and there is already friction between Mercedes team-mates Lewis Hamilton and Nico Rosberg.
The Briton Hamilton beat his German team-mate for victory at the Chinese Grand Prix Sunday as they rebounded well from a surprise defeat against Ferrari's Sebastian Vettel in Malaysia two weeks ago.
Hamilton beat Rosberg for the 2014 title in an at times tense relationship, and has also finished ahead of him in the three 2015 races to lead the championship.
Rosberg was visibly unhappy about the latest defeat and had already during the race questioned via team radio why Hamilton was driving rather slow after pit stops as the charging Ferraris of Vettel and Kimi Raikkonen were closing in.
He was more explicit at the post-race news conference and bluntly accused Hamilton of compromising his race after Hamilton said he was looking at his own pace only to conserve his tyres.
"It's just now interesting to hear from you, Lewis, that you were just thinking about yourself with the pace in front, and necessarily that was compromising my race," the German said.
"It was unnecessarily close with Sebastian ... and also it cost me a lot of race time as a result because I had to cover him and then my tyres died at the end of the race because my stint was just so much longer. So I'm unhappy about that, of course, today."
Hamilton would have none of it and retorted: "It's not my job to look after Nico's race. My job's to manage the car and bring the car home as healthy and as fast as possible - and that's what I did.
"I didn't do anything intentionally to slow any of the cars up. I just was focussing on myself. If Nico wanted to get by he could have tried but he didn't."
More friction between their drivers will be the last thing Mercedes will want now that they seem to have a real title rival in Ferrari.
But Mercedes motorsport chief Toto Wolff downplayed the incident, insisting: "there was no animosity."
"It is understandable that Nico acted so emotional. It is also understandable that Lewis played it that way."
The second world title and strong 2015 start has made Hamilton, who came to Shanghai with a new hairstyle and wearing two thick golden necklaces, super confident.
He said said that the team also asked him during the race to drive faster as Vettel and Raikkonen closed within four seconds of the top, but stated that tyre management was his top priority - after Vettel had outsmarted Mercedes in that area in Malaysia.
"I mean I'm out there driving as hard as I can but within the constraints of the tyres. They kept coming on the radio and asking me to pick up the pace and I'm kind of 'well, I'm trying to manage these tyres,'" Hamilton said.
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