WESTERN Bulldogs midfielder Mitch Wallis could return within nine months after undergoing successful surgery to repair his broken left leg on Sunday.

Wallis, who broke both his left tibia and fibula bones in Saturday's loss to St Kilda, underwent surgery at the Avenue Hospital in Melbourne on Sunday afternoon and had the injury plated by surgeon David Young.

Young was optimistic about Wallis's recovery prospects when contacted by AFL.com.au on Monday afternoon.

The leading orthopaedic surgeon had earlier forecast a 12-month recovery for the midfielder, telling Triple M on Sunday that was a realistic timeframe.

He now believed that could be reduced to inside nine months after a successful operation.

Young said the injury was identical to that suffered by teammate Jake Stringer when the Bulldogs forward was playing in the TAC Cup prior to being drafted.

Stringer will be a mentor for Wallis in his recovery, Young said, having made a full recovery himself.

Wallis, 23, took to social media on Monday to thank supporters.

Successful surgery!! Humbled by the support and messages.. #I'll be back go dogs

A photo posted by Mitchw@llis (@mitchywallis) on Jul 24, 2016 at 5:55pm PDT

Young was also expected to perform a traditional knee reconstruction on Bulldogs forward Jack Redpath, who tore his anterior cruciate ligament in Saturday's match.