ST KILDA have defended raising the so-called "tunnelling" tactic after Sydney coach Paul Roos described the AFL controversy as a "slur" on the Swans.

Roos has strongly criticised Saints chief executive Archie Fraser for not going to the Swans first with St Kilda's concerns.

St Kilda have sought clarification from the AFL, with the club believing Swans defender Craig Bolton deliberately used tunnelling against Saints captain Nick Riewoldt last Saturday night at Telstra Dome.

Tunnelling is better-known in basketball and involves a player deliberately bumping an opponent's legs or lower body once he has jumped off the ground.

Roos said he, Bolton and the Swans were surprised by comments attributed to the Saints in the media and insist they are all totally unaware of the tactic.

Roos says he has no issue with St Kilda, but feels Fraser should have gone through the proper channels before speaking to the media.

"We made that very clear absolutely, we just needed to get that across to Archie and the St Kilda footy club," he said.

"I spoke to (current St Kilda coach and former Swans assistant Ross Lyon) today and he and I are fine," Roos said.

Late on Wednesday afternoon, Fraser was quoted in a club media release saying he had spoken with Swans counterpart Myles Baron-Hay.

"Our clubs continue to have a good relationship," Fraser said.

"None of this was ever intended as an attack on Sydney.

"As a club we raised the question to seek clarification of the rules and it's up to the AFL to interpret the rules for the competition."

But the AFL see the matter as nothing more than a couple of missed free kicks during the St Kilda-Sydney game.

The league's view is that so-called tunnelling is already covered in the rules of the game under prohibited contact.

"The AFL has actually already had this on the umpiring DVD, where you usually see it paid is at centre-bounce ruck contests where one ruckman will step under another," said AFL media manager Patrick Keane.

Brisbane key forward Jonathan Brown also defended Bolton today, but wants the AFL to monitor this sort of contact because of the potential danger if a player is "tunnelled" and then hits the ground awkwardly.

"It definitely is dangerous, but I can see how the defenders get themselves in the situation, if the forward jumps early the defender sometimes has nowhere to go except sit underneath him," Brown said.

"No doubt the defender is going to try and influence the contest as much as he possibly can.

"But I have played on Craig Bolton a few times and I haven't had any issues with Bolts doing that, I probably don't jump as high as Riewoldt, that's probably why I don't get tunnelled.

"It is something worth the AFL keeping an eye on."