Dani Pedrosa will fly back to Spain this evening to undergo surgery for a right collarbone fracture sustained in Friday practice for the Japanese MotoGP.
The Repsol Honda star, winner of last year's race, was dramatically fired into the air at the apex of the 90-degree corner, while on an out-lap in the closing stages of the afternoon session.
Some riders, including Valentino Rossi
, suspect a sharp drop in temperature contributed to the numerous FP2 accidents.
“I'm obviously very sad about what happened, as I was looking forward to racing in Japan at Honda's home circuit and one of my favourite tracks," Pedrosa said.
"I was on the out-lap of my last run in FP2 when I momentarily lost the rear entering turn 11, and when the tyre found grip again it launched me in the air.
"There's not much more to say; now I just want to focus on recovering in order to get back on my bike as soon as possible."
Motegi is the first of three races in three weekends, meaning many suspect Pedrosa will not be seen on track again until November's Valencia finale.
However, the Spaniard's exact recovery time will not be known until the surgery is complete and at present he is only withdrawn from Japan.
Pedrosa - whose career has been dogged by collarbone injuries - will be replaced by HRC test rider and former 250cc world champion Hiroshi Aoyama
Team-mate Marc Marquez, who is on the brink of winning this year's MotoGP title, added: "I'm very sorry for Dani, as it seemed that he was really coming back to his usual speed. I just wish him a quick recovery."
Pedrosa's injury is likely to cost him fourth in the world championship to Suzuki's Maverick Vinales.
Eugene Laverty also required medical checks after a big accident, just moments after Pedrosa. The Irishman was sent for scans, which ruled out any serious injuries and he is hoping to be cleared to continue by cirucit medical staff.