John McPhee has been ruled out of this weekend's Indonesian Moto3 Grand Prix after fracturing two vertebrae during a Supermoto training accident.

Fortunately for the Scotsman, who finished fifth on his debut for the Sterilgarda Husqvarna Max racing team in Qatar, the fractures are 'stable and there is no need for surgery'.

McPhee is now starting rehabilitation 'with the intention of returning for the Argentine Grand Prix, which will be held on April 3'.

A statement from Max Biaggi's team confirming the injuries also noted that McPhee, who made his grand prix debut back in 2010 on a 125cc two-stroke, has never missed a grand prix due to a training injury before.

Assuming no last-minute replacement is found, Ayumu Sasaki, who led for much of the Qatar race before suffering a near highside and fairing damage, will be the only Max Racing rider at Mandalika this weekend.

Unlike MotoGP, the Moto2 and Moto3 classes did not have a pre-season test at the new Mandalika circuit, which has also undergone 25% resurfacing ahead of this weekend.