Four of Audi's DTM squad got the chance to try out the marque's R10 TDi sports prototype on the eve of the new touring car season, and are now casting one eye towards the Le Mans 24 Hours and the chance to race the machine for real.

Mattias Ekstr?m, Lucas Luhr, Alex Pr?mat and Mike Rockenfeller completed approximately 1400 kilometres with the diesel-powered machine during a development test for the 24 Hours at Paul Ricard, and are now apparently in the frame should Audi decide to enter a third car for the French classic.

Even though some had previous sports prototype experience - and, in Premat's case, recent F1 experience - all four were impressed by the power and torque produced by the V12 TDi engine during the test.

"The thing just takes off like a rocket in every gear," Rockenfeller said with a broad smile, "You get used to everything with time - but this engine is simply amazing. It's a fantastic feeling every time you hit the throttle."

Luhr, who - like Rockenfeller - is used to LMP2 machinery from German rival Porsche and used to compete against Audi in the American Le Mans Series, admitted that he was surprised just how noticeable the heavier weight, stipulated by the LMP1 regulations, was.

"You notice that the car is 150kg heavier, particularly when you brake into the corners or have to change direction rapidly," he revealed, "However, the R10 is very driveable, reacts precisely to changes and is great fun to drive - and obviously the engine power is staggering."

Pr?mat, who made his F1 debut with Spyker in China last season, got a taste of the R10 on his 25th birthday and was equally impressed with the way Audi's sportscar programme was run.

"It's incredible to see just how professionally the Audi team works," he said, "The R10 is simply unbelievable - it may be a TDi, but it has the power of an F1 car. I'm extremely grateful that Audi gave me the opportunity to test this car - it was a nice birthday present."

Ekstr?m, meanwhile, was able to compare the new car to its predecessor, the petrol-powered R8, but was amazed at the advances that had been made.

"First of all, I need to sleep on this experience for a few days and analyse the whole thing, because it was so amazing that I drove every lap with adrenalin pulsing through my veins," the Swede enthused, "I felt immediately at home in the car, but I need more experience to keep calm. The power, torque and downforce are phenomenal and obviously completely different to the DTM car. I could only have kept up in the slow corners with my A4."

All four drivers made such a good impression that they are now first choice for the cockpit for a third R10, should the entry be confirmed, at the 24 Hours in June.

"This test was very positive since all four drivers had prepared themselves extremely well for this opportunity and remained focused on driving the R10," explained head of motorsport Dr Wolfgang Ullrich, "All four approached the task in the professional manner I expected. They all immediately reached an exceptionally good level and more than fulfilled my expectations."