COACHES and match analysts at the AFL have warned against making bold predictions about the future of ruckmen after the opening round of matches sounded a warning for their effectiveness in 2021.  

In a round of fast, entertaining football that saw the conversion of rebound 50s to inside 50s increase significantly, ruckmen were the unexpected victims, caught between contests and regularly bypassed. 

Melbourne big man Max Gawn admitted at half-time of the Demons' win against Fremantle that he needed to find a role for himself in the match, with general play stoppages significantly down.

With a particular focus on lower interchange numbers, West Coast coach Adam Simpson also said the new rules and resulting game style could put the future of power athletes like Nic Naitanui in doubt.

The new rules, including the stand on the mark rule and reduced rotations, worked exactly as planned in round one for the AFL's game analysis team.

The ball transitioned from defensive 50 to inside 50 at a much greater rate, and there were fewer opportunities for teams to lock down defensively and force stoppages.

The stat that appeared to please the AFL most was the defensive 50 to inside 50 conversion of 26.7 per cent.

There was also a reduction in ball movement around the boundary, down from 43.3 per cent in 2020 to 40.6 per cent in round one as players looked to take more dangerous corridor options.

This, combined with fewer general play stoppages (49.3 a game in round one), meant ruckmen were less involved in the play.

Simpson said fewer rotations and a return to full-length games meant powerful ruckmen like Naitanui could make way for endurance athletes.

"Players like Nic will be hard to keep in the game," the coach said this week. 

"The endurance players will step up and we'll get what we get. I suppose it's good that Nic is getting to the back end of his career and not the start.

"I'm sure he would adapt, but it would be more of a challenge.

"If it's going to trend this way we need to look at the types of players we draft."

While considering the future of power athletes, Simpson also said it was worthwhile watching the first four rounds unfold before assessing trends in the new season.

He recalled a round one clash against Brisbane in 2016 when both teams scored over 100 points and he thought "the game's changed". 

"By round five it went back to what it normally was, so I think we just need to see how the next three or four rounds look before we jump to any major conclusions," Simpson said.

Fremantle coach Justin Longmuir was also cautious not to make any predictions about the future of ruckmen and said the centre bounce remained as important to teams as it always had.

"I think the game will change over the next six weeks and if we're still seeing the same thing in six weeks' time then we might need to go a little bit smaller and get a few more runners into the side," he said.

"(But) I imagine it might get a little bit more congested as the season goes on and players get a little bit more cumulative fatigue in them.

"Let's just wait for the season to settle before we make any bold predictions, especially about ruckmen."

The form of Brodie Grundy on Thursday night was also a timely reminder that ruckman can still influence a match in a major way.

The star Magpie had 51 hit-outs as stoppages increased and 16 disposals to be one of the most effective players on the ground, bouncing back from 39 hit-outs and 11 disposals against the Western Bulldogs in round one.

Grundy proved the AFL's big men are just as capable at bouncing back to form and they should find a way to influence matches under the AFL's new rules.