Thirty degrees in the shade, high humidity and asphalt temperatures of up to 43 degrees caused especially difficult circumstances on the Florida track.
McNish showed the potential of the 650bhp V12 TDI engine with a record-breaking pole-position time in qualifying. Because the heat exchanger had to be replaced after the morning warm-up, Capello was forced to start the R10 TDI from the pit-lane starting his chase from the back of the field.
It took Capello half an hour to move the Audi from 35th and last position to second just behind the sister car of Frank Biela (Germany), Emanuele Pirro (Italy) and Marco Werner (Germany).
Shortly before the end of the second hour, the McNish/Capello/Kristensen Audi took the lead and remained at the head of the field to the chequered flag, McNish also setting a new race lap record.
The Biela/Pirro/Werner Audi R10 TDI that had started alone from the front row led the race for the first two hours but did not reach the finish after it was withdrawn just before one-third distance due to an overheated engine. Shortly after the start of the race, the telemetry system had stopped working and Audi Sport’s engine technicians received no data.
When Werner reported high water temperatures via radio during the fourth hour of the race, the second placed R10 TDI was called into the pits. The team discovered the radiators were completely blocked by tyre rubber. After cleaning the radiators, the temperature sank immediately.
However, Team Audi Sport North America decided to withdraw the second placed R10 TDI from the race as a precautionary measure, because the engine had been running with significantly high temperatures for an extended period.
For Audi, it was a seventh consecutive Sebring race victory while Kristensen became the first driver to win America’s most famous endurance race for a fourth time, achieving another record after his record seventh Le Mans victory from last year.
Audi boss Martin Winterkorn was there and said: "Audi has once again written motorsport history, this time by being the first manufacturer to win an endurance race with a diesel powered sportscar. This impressively confirms the efficiency of the modern TDI technology. It is especially remarkable that this success was achieved at the very first race of the new Audi R10 TDI. The whole team from Audi Sport and the Technical Development of Audi has once again done a great job. I thank everyone who is participating in this ambitious project."
Meanwhile McNish, who claimed a Grand Slam by setting both the fastest qualifying and race laps combined with his second-ever Sebring race win, added: "The whole team should be very proud - we have created a little piece of history. In a few years time, people will look back and realise this was a monumental moment, not only in Audi Sport history, but also in motorsport where the first ever Diesel engine won an international sportscar race. We all worked very hard for this one."
The next race for the Audi R10 TDI, which features an all-aluminium V12, turbocharged 5.5-litre diesel engine producing 650-hp, is the Le Mans 24 Hours (17-18 June) - the twice around the clock marathon Audi has won five times since making its début in 1999.