Monster Energy Kawasaki's Ryan Villopoto won't be defending his outdoor number one plate in 2012.

Monster Energy Kawasaki has confirmed that Ryan Villopoto will not defend his AMA Motocross title in 2012 after injuring his knee at the Seattle AMA Supercross round last Saturday night.

The two-time AMA Supercross and defending AMA Motocross champion will undergo surgery on his knee this week, a bitter disappointment after recording a perfect championship season one year ago.

“I’m pretty disappointed right now,” said Villopoto. “I have trained hard for this season and even though I won the supercross title, I really wanted to defend my outdoor championship.

“I’ve been through injury before and I know how hard I have to work to get back.”

Villopoto is coming off of a dominant 16 months where he earned two AMA Supercross titles on the strength of 15 wins, the AMA Motocross Championship with three wins and also the richest payday in supercross with a million dollar win at the Monster Energy Cup.

Get well soon RV, from all of us here at MotoOnline.com.au.