By Joe Davies: ITV News Digital Producer
Formula One legend Jim Clark was once asked in 1967 how he was enjoying being Graham Hill's team-mate at Lotus.
The Scot replied: "I'm not. He's my team-mate."
Even before the days of live telemetry providing the finest detail on a driver's every move, their performance against the man on the other side of the garage was scrutinised the most. The only driver with the same equipment, nothing matters more in Formula One than beating your team-mate.
But it hasn't always been that way.
In 1957, Stirling Moss and Tony Brooks were joint winners of the British Grand Prix at Aintree, after sharing driving duties in the Vanwall.
It was the first time that a British built car had won a Formula One World Championship race - and the third and final time that a Grand Prix would be won by two drivers in a shared car.
It is hard to imagine such a scenario now.
Almost 60 years on, this weekend the sport returns home to the Silverstone circuit where Formula One was born in 1950, with bosses at the Brackley-based Mercedes team warning of major consequences if there is a fourth crash in six races between their warring team-mates Lewis Hamilton and Nico Rosberg.
The pair have been given a "final warning" and a licence to race with no threat of team orders just yet, following their final lap collision while leading the Austrian Grand Prix a week ago.
Friends during their karting days, their relationship since becoming team-mates at Mercedes has been turbulent to say the least, thanks to numerous on-track skirmishes in a car that is the class of the field for the third season in a row.
Hamilton, who is chasing his third straight British Grand Prix win and Rosberg's 11-point championship lead, said on Thursday that Mercedes' beefed-up deterrents issued to the two drivers since Austria "doesn't really change anything".
But success for Rosberg on Sunday might do just that, if Hamilton's victories at the Northamptonshire track in 2008, 2014 and 2015 en route to his three world titles is an omen.