The Troy Lee/Red Bull/KTM rider went down hard during a tricky section of the tough Unadilla track and was slammed in the back by his dirtbike.

Nelson was transported to hospital in Cooperstown, NY where he is waiting for swelling to go down in his back before undergoing surgery.

At this time he has reported having limited feeling from his waist down.

Nelson posted this update to his fans.

We are hoping Jessy has a quick recovery and we’ll keep you all up-to-date as we find out more information.

Photo: Simon Cudby