BRUCE has signed off from Australian football. He will not be talking footy on Monday nights, well not on the nightly news at Seven or any of the panels that pop up like mushrooms across winter on television, radio and now the ever-increasing podcast gallery.

Bruce McAvaney has after about 1000 matches put down the microphone at AFL games - to be a fan again. And Gold Coast midfielder Hugh Greenwood summed it up by noting McAvaney's "retirement" announcement belonged amid the heavy hits delivered during the COVID-strained 2020 ... and is a timely reminder that the popping of champagne corks on January 1 did not clear away the pandemic.

This weekend - with Port Adelaide's pre-season trip to Perth to play West Coast at Leederville Oval on Sunday cancelled out of concerns for potential border closures with COVID outbreaks - tells how the AFL fixture is again a fragile concept.

For the continued uncertainty this brings, there is one sure thing as to the lead item on any Monday night talkfest in Australian football this week: AFL football boss Steve Hocking's continued fight against the defensive themes in the coaches' playbooks.

At Alberton Oval during Saturday's Port Adelaide-Crows trial - won by Port Adelaide by 52 points from 35 scores (18.17) - was the field umpires having a greater emphasis on looking for holds, blocks and pushes on forwards in marking contests.

Port Adelaide defence coach Brett Montgomery was very diplomatic post-match saying: "Everything that comes across our desks (as coaches from Hocking's office) is the want to speed the game up; to make it more attractive.

"Forwards getting the ball; a better look at marking contests is consistent with that."

Every Port Adelaide supporter who has groaned - and yelled in frustration - in watching All-Australian key forward Charlie Dixon denied free kicks after interference in marking contests will sing in unison "Hallelujah"!

Every football fan who admires Port Adelaide captain Tom Jonas strain every muscle and reserve of energy to deny a forward a set shot at goal will sit uneasy. By year's end someone will need to commission Champion Data for a breakdown on free kicks - and the very certain increase from previous years - paid in marking contests.

Interpretation of the rule book will dominate the early Monday night talkfests, particularly with the new "stand rule" that punishes the man on the mark with a 50-metre penalty should he even lift his heels ...

The inevitable question in every team meeting across the national AFL platform is: "Why stand the mark?" Is it not better to concede a metre or two from the mark rather than run the risk of giving up 50 metres - and a damaging shot on goal?

Australian football now runs the risk of mirroring the world game where no one stands the spot of a free kick until there is a need to protect the box with a wall, be it one man or more. Defences will fold back - space will be congested. Not quite the AFL mantra is it?

Bruce McAvaney will be spared the challenge of masking any frustration in his calls in the Channel Seven commentary box .... The rest of us will be annoyed by pedantic umpiring calls; fascinated by how players adapt to avoiding the 50-metre penalty; amused by how coaches dodge the debate in post-match media conferences and applaud the first talking head to capture the fans' views on Monday nights.

Bye bye (or sayonara until the Tokyo Olympics) Bruce. And hello AFL Season 2021.