A trio of Channel 7 pundits are in the running for the open vacancy left by legendary commentator Bruce McAvaney, per The Herald Sun's Scott Gullan.

McAvaney announced he would be stepping down from his duties with the network's AFL broadcast, turning his attention to this year's Olympic Games and horse racing.

The 67-year-old leaves an irreplaceable legacy and void in Channel 7's prime time broadcast, with the race for his successor now a key focus for the network on the eve of the 2021 AFL Premiership season.

“I felt like I got to a stage in my career where I had to reduce my workload,” McAvaney told Seven News.

“I’m going to miss it enormously, I just visualise when Richmond and Carlton run out there in round one, and the ball is bounced, I’m going to climb a wall somewhere.

“I’m going to have to move on and just be a fan like everybody else.”

James Brayshaw, Luke Darcy and Hamish McLachlan will all be trialed throughout the first half of the season to see who blends best with McAvaney's now former partner-in-crime Brian Taylor.

Brayshaw firms as the frontrunner to take over the reigns from McAvaney and will be placed into the spotlight early on with his Triple M colleague, Taylor on Friday nights.

Darcy and McLachlan will also get a fair audition, with the latter set to remain in his role of hosting the Friday broadcast before joining Darcy in the pundits box for Saturday night fixtures.

McAvaney's late bombshell has left Channel 7 with no option to look externally for a replacement.

Channel 7 commentator Jason Bennett has received plenty of praise for his game calling in the AFLW and VFL, and will be a viable option waiting in the wings for the network.