Clarke, who turned 18 in February, got the SOS call this week to join Jeff Hardwick's Australian run Shell Advance Honda team as a replacement for injured Englishman, Chris Walker.

He had to make a hasty exit from St Francis College in Crestmead, south of Brisbane to get ready for the flight.

"I got the call in the middle of maths class," said Clarke. "It was a real big shock. Ever since I saw Wayne Gardner racing when I was four or five, I wanted to be World 500 Champion. We had plans to go over to Europe later in the year to see a Grand Prix but I didnšt think I would be racing in one this soon."

He will take a seat on a Shell Advance factory kitted Honda V-twin this weekend with an opportunity for more rides in the blue-riband class should Walker's injuries continue to consign him to the sidelines.

The head injuries Walker sustained in a high speed crash at the Dutch TT in Assen last month are still cause for concern, and despite his brave effort to race in his home GP at Donington on 8 July, he has been advised to sit out this race.

"It will be the most powerful and the lightest bike I have ever raced so it will be a step up and a great challenge," said Clarke.

"If I can finish amongst the leading V-twins, I will be happy. It might be a bit weird to see the likes of Rossi, Biaggi and Capirossi on the track with me, but I will have to try to slip in behind and stick with them for as long as I can."

Young British rider, Leon Haslam, is expected to take over Walker's full factory four-cylinder Honda NSR500, while Clarke will take over Haslam's V-twin.

Clarke was enjoying a successful debut full-time season in the Shell Advance Australian Road Racing Championships, leading the 250cc Production and running a close second in the 600cc Supersport classes with his Tony Armstrong Springwood Suzuki team before he was called up.

Armstrong is confident his young charge has the right ingredients to make a successful career in Grand Prix racing.

"In the two years he has been riding in the Australian road racing series, he has never crashed. He has never even bent a lever," said Armstrong. "The only crash he has ever had was in the United States in July last year when he went over to race in an Aprilia 250 Challenge race. Even that came after he had secured pole and was leading the race by more than three seconds."

Clarke's strong relationship with his associate sponsor, Shell Australia, has created this fantastic opportunity for the youngster.

"My mates ribbed me a bit, joking about what a tough life I have, skipping out of school to fly to Germany to race a motorbike. They will all be gathered around a TV on Sunday night to watch me so I hope I go okay," he said.

The Shell Advance Honda team has a history of providing Australian's with a springboard into the top class, with Garry McCoy and Anthony West both having ridden with the team in its four-year history.

Brendan Clarke ­ Profile

• 1987 ­ Started racing aged 4, dirt bikes on oval tracks
• 1990 ­ QR50cc Queensland Champion
• 1993 ­ 60cc Australian Champion
• 1995 ­ 60cc and 80cc Australian Champion
• 1998 ­ Started Road Racing, 80cc road bikes
• 2000 ­ Youngest 250cc Aprilia Challenge rider, won last two rounds of the series to finish a close second in Championship
• 2001 ­ Has won all five rounds of the 250cc Aprilia Challenge Series, setting lap records at each round. Currently leads 250cc Shell Advance Road Racing Series and runs a close second in 600cc class.