MELBOURNE's Max Gawn has adopted a unique approach to try to avoid giving away more ruck interference free kicks. 

The star big man has trialled wearing a sling-like device at training in a bid to prevent him from using his off-arm to keep opponents at bay in ruck contests, which, under AFL guidelines, is considered an illegal tactic. 

The stretch-band wraps around Gawn's trailing arm so that he contests the ruck with more of a bent arm. The star big man was practicing the technique with ruck coach Greg Stafford at a training session last week. 

Gawn was mystified after being penalised four times for using straight-arm blocks against St Kilda's Billy Longer in round 21, with Melbourne seeking an explanation from the AFL's umpiring department about why the free kicks were paid. 

Against the Western Bulldogs in Ballarat on the weekend, Port Adelaide ruckman Patrick Ryder was pinged on three occasions for similar incidents to the ones that stumped Gawn.

AFL umpires coach Hayden Kennedy gave AFL.com.au an explanation about the ruling last week: "Basically, both players have to have the ability to contest the ball. If there is a straight arm by one of the players, when the other player is contesting the footy, that's when it becomes a free kick."

AFL.com.au knows of one example this year where an opposition club has made the umpiring department aware of a ruckman using the straight-arm block technique to his advantage.

It is also believed some clubs are becoming increasingly frustrated that certain players, who they believe are utilising straight-arm blocks in ruck contests are not being penalised as heavily as others.

Gawn said he now had more clarity about the ruling.

"I sort of had a rough idea (that it was in the rule book), but they'd just never been paid, so it was a bit of a surprise to me when I was out there," Gawn told SEN on Wednesday.

"They pay some and they don't pay others at the moment, but I've got my head around it now.

"I have been doing it for a long time. It's a straight-arm rule that is there, so the umpires are just paying what is in the law book, so it is something that I have been training on in the last two weeks keeping my arm a little bit more bent. 

"I was considering taping my elbow and showing the umpires, because you can’t actually straighten your arm when you tape your elbow." 

Despite the increased focus on the straight-arm block tactic, statistics do not show any definitive spike in free kicks paid for a block in a ruck contest, with 14 coming in rounds 20 and 21 and only four in round 22. 

Those figures are comparable to the number of free kicks paid for blocks in rounds eight, nine and 10 (14) and less than rounds one, two and three (16). 

Kennedy stressed there had not been an increased focus from the  umpiring department on the straight-arm block ruling.

Kennedy said it was discussed at the umpires' meeting on Tuesday night, although that was only to ensure the officials were clear about what constitutes a free kick. 

"The interpretation about this rule hasn't changed," Kennedy told AFL.com.au. 

"Our coaching around ruck blocks has been consistent through the year.

"It's a difficult one because the umpire bounces the ball, he backpedals and he's got to see two guys jumping in front of him – that's why some get picked up and that's why some others don't."