'Big shock' sends Fabrizio into retirement.

MS Aprilia Racing's stand in for the injured Shane Byrne, Michel Fabrizio, had a disappointing and painful end to his one-off ride at the Estoril GP in Portugal this weekend.

With Shane Byrne expected to be fit for the Twin Ring Motegi GP later this month, Fabrizio was hoping to claim a top 15 finish on his first race on board the Cube.

But the promising 19-year-old was forced to retire after 11 laps, due to arm injuries sustained when a first lap wheelie sent his Cube into an arm-wrenching tank-slapper.

"I'm very disappointed," commented Fabrizio."On the first lap I had a big wheelie accelerating hard and when the bike came down, the handlebars went into a violent shake.

"It was a big shock on my arms and wrists and after a few laps I was struggling to hold on," continued the Roman. "This is not how I wanted to finish my first ride for Aprilia. I have to say a big thanks to Aprilia and the team for this great opportunity, and hopefully it won't be my last. I have learned a lot and enjoyed the experience, if not the result."

Fabrizio was taken for precautionary checks in the circuit's medical centre, but doctors confirmed he'd not suffered any serious injury.

Fabrizio is now expetced to return to Harris WCM team for the Japanese Grand Prix.