SYDNEY Swans coach Paul Roos has described North Melbourne's reaction as sending "mixed messages" and "strange" after it was revealed the Swans had 19 men on the field for a brief period of the sides' drawn clash on Sunday.

The Swans received a $50,000 sanction from the AFL on Tuesday night for having the extra man on the field late in the game, with the League also revealing it considered awarding the four premiership points to the Kangaroos.

"It looks like Dean [Laidley] probably hasn't spoken to James [Brayshaw] because there's a little bit of mixed messages coming out of there," Roos said on Wednesday.

"I thought they [North] handled it really well after the game and Monday and early parts of Tuesday but they must've had a meeting on Tuesday to say that what they'd said on Monday and Tuesday morning wasn't correct.

"That's their decision to take the tact they have since yesterday lunchtime. And we've just moved on. It's a little bit strange the way they handled things. It changed significantly ... for what reason, you'd have to ask them.

"I read after the game that Dean wasn't concerned about it. We worked out it was 18 seconds [that the 19th man Jesse White was on the field at Telstra Dome]. The loose man was down the back end of the ground and nowhere near the contest. But obviously James had a different position from where he was sitting and clearly saw it differently."

In recent seasons, the Western Bulldogs and Hawthorn have been fined $7500 each for having an extra man on the field, however, the AFL has argued that the severity of this penalty is a result of the interchange error happening at a crucial stage of the game.

Roos added that he felt North's reaction may have influenced the decision to significantly increase the fine.

"I think it has," he said. "It's probably a little bit strange that the precedent has been set at $7500 and it's happened twice before so it's not as if it's the first time it's happened so they've had an opportunity to address rules.

"You can't be critical with the AFL, they were very professional with us. But it's a reasonably significant jump in the fines."

While admitting his club had made a mistake, Roos said he felt it was appropriate that the League addresses the issue of interchange, particularly when it becomes more frantic.

"At that particular time, who's in charge of the interchange?" asked Roos. "Is it the AFL or the clubs' responsibility? With the amount of interchanges going on it's time to make sure there are some changes and things like this don't happen again.

"There is one guy down there but I've not thought through how it could be better managed. But at least you'd need one guy working with each team and maybe we should look at the NFL where there's a field penalty.

"While this is the third public time, I'd be staggered to think it hasn't happened 10, 12, 14 times when guys have gone on for 10 or 15m then thought, 'hang on' and run back. I feel for the interchange guy.

"I reckon there are a lot of times when there are 16 or 17 guys on the pitch, not that it's illegal but the point is it's a bigger issue now than ever before with the amount of rotations."

Roos speculated that the current interchange protocols were put in 10 years ago when there were significantly fewer interchanges.

"And if you want to be technical, it actually disadvantaged us," he added.

"At the last kick-in, Darren Jolly, who we yelled to come off, was on McIntosh. The guy who marked it was McIntosh because our loose man down back was Craig Bolton. So it disadvantaged us because it gave them a chance to score that otherwise wouldn't have presented itself."

Roos finished with a wry smile: "It's all part of AFL footy."