REIGNING Brownlow Medal winner Tom Mitchell has signed an extension to his long-term deal with Hawthorn, ensuring his future with the club until at least the end of 2023.

Already tied down with the Hawks until 2021, Mitchell has penned a two-year extension.

Mitchell claimed last year's Brownlow Medal after a prolific season in which he averaged 35.3 disposals per game, but hasn't played this year due to a broken leg.

He will be sidelined for the entire year, having suffered the injury in January.

"We're really pleased to have Tom re-commit to the club for the long-term," Hawthorn footy boss Graham Wright said in a statement on Tuesday.

"He's such a valuable player for us and we see him playing an important role for a long time to come.

"His work around the stoppages and his ability to accumulate high disposal numbers is second to none.

"Tom has been attacking his rehab program with great intent over the past few months, and we're really looking forward to having him back out on the park."

Mitchell has played 46 games for Hawthorn, having played 65 games for Sydney.