Things couldn't get much worse for Aussie AMA MX/SX superstar, Michael Byrne, after crashing out while leading the first 450 moto at the Unadilla round of the Lucas Oil AMA Pro Motocross Championship, which lead to a broken leg. Only a few races back after recovering from a cracked vertebrae, Byrne will now be forced back to the sidelines.

The broken tibia will be a major disappointment for the BTO Sports/Palmetto Suzuki rider, who earlier revealed via twitter that he was supposed to be racing for Team Australia at Lommel in the 2012 Motocross of Nations. Motorcycling Australia was due to make the Aussie MXoN team announcement today, but will now be forced to re-think the decision of who will fill the MX1 position.