By Ian Parkes Four-times Formula One world champion Alain Prost fears Nico Rosberg and Lewis Hamilton risk damaging their relationship in the heat of this year's intense fight for the title. Hamilton and Rosberg have known one another since their karting days, even working as team-mates, before reuniting last year following the former's arrival at Mercedes. The duo have always been civil and cordial towards one another, but as time has worn on this season that has shown signs of slowly changing. Scroll down for videos... Frenemies: Lewis Hamilton (R) and Nico Rosberg (L) could fall out in race for the Driver's Championships
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Mercedes drivers Lewis Hamilton and Nico Rosberg risk a bust up, warns Alain Prost
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Hamilton leads the German by three points in the Drivers' Championships
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Prost had an intense intra-team rivalry with Brazilian Ayrton Senna
@placeholder has been forced to settle for the runner-up spot behind his team-mate on each occasion, and it is clear that this has rankled.