The accolade is presented to the season's best player under 21 years of age.

Williamson polled 12 votes in seven rounds, including maximum votes in round 12 against Horsham United and round 13 against Nhill.

The Rats' vice captain previously won the Rookie of the Year award in 2010, finishing equal fifth in the Toohey Medal count alongside Nhill's Simon Brearley, also polling 12 votes.

Williamson said he never expected to win the award a second time.

"I was surprised with how I did because I didn't think I had that good of a year. Obviously I must have done something right to get the attention of the umpires," he said.

"In my own mind I thought I could have done better, playing more consistently rather than good in patches."

This season was a disappointing one for the Rats, who chalked up five wins for the season to finish seventh.

"Overall we could've had a good year if not for injuries. I think we did really well with what we had," Williamson said.

Williamson said he would line up for Ararat next year and was looking forward to living up to the Rats' potential.

"A lot of the guys think we're due to make finals," he said.

"Hopefully we can recruit well and get some good numbers on the park and give some of the better sides a run for their money next year."

The Toohey Medal award for the season's best and fairest player was presented to Horsham Saints' Phil Butsch, who polled 24 votes, one more than last year's winner, Warrack Eagles' Steve Schultz.

Horsham onballer and 2012 Greg Binns Medal winner, Nick Pekin finished third on 19 votes.