Jonas Folger has been forced to withdraw from this weekend's MotoGP Japanese Grand Prix due to a mystery illness.
The Tech 3 Yamaha rider has been ordered to return to his native Germany for further tests after doctors deemed the MotoGP rookie unfit to compete at Motegi this weekend.
Folger, who had travelled with the team to Japan, has been feeling under the weather since the Misano round last month.
The 24-year-old is lying 10th in the championship following an impressive maiden campaign in motorcycle racing's top tier.
“I came to Japan and was motivated for these three flyaway races, but I've been feeling really weak since the Misano and Aragon rounds,” said Folger in a team statement.
“On arrival here, I have been struggling with my energy levels, even leaving the hotel room was impossible for me, and unfortunately, I had to miss some Yamaha events, which I'm very sorry for.
“I met with Hervé (Poncharal, Tech3 team manager) on Wednesday night and we agreed to go for a check with the doctors this morning. I met with Dr Charte and the Clinica Mobile team and they have advised me to return to Germany right away for a series of blood tests.
“I've had Epstein Barr virus in the past and it's a possibility that this has flared up again and resurfaced, but we can't be sure until I've had these tests in Munich.
“I'm really sorry for my whole team and Yamaha at their home race and would like to thank them for all their support.
“Also sorry to my personal sponsors, I appreciate them all standing by me at this difficult time. Now we must remain positive and aim to come back stronger.”
The team is yet to announce if Folger will be replaced for this weekend and further rounds should he be deemed unfit to race.