Defending 450 Pro Motocross champion Zach Osborne is officially out for the remainder of the 2021 season, subsequently ending his title defence.

Osborne sustained a back injury while training in the mid part of the Monster Energy Supercross season and opted to sit out the remainder of the season to let the bulging disk in his lumbar spine heal.

He returned to riding ahead of the opening round of Pro Motocross and appeared to be fully healed and ready to battle for his second premier class crown, taking fifth in moto two at the opening round at Fox Raceway.

Osborne’s fate changed at the second round, as he was clearly dealing with issues in the second moto as he’d end with a DNF. It’s now been confirmed that he’ll miss the remainder of the season to focus on getting back to 100 percent.

“I’m bummed to say the least,” Osborne explained. “This injury has been a big setback with no clear path to 100 percent but I feel I’m on a good path now and I just need to give my body the time to heal itself.

“Myself, along with the team, made the decision to pull the plug and be ready for 2022. It was a tough decision in an already-trying year but I believe I can be back to 2020 form with this time away to heal up. Thanks to my team and fans for the support through this!”

The season will continue without the reigning champion this Saturday, 19 June, on the heels of a two-week break at High Point Raceway.