BARRY Hall might get away with it this time, the contact with his forearm to Shane Wakelin's head on Saturday night at best glancing.

A worst-case scenario could be an attempted strike, which, even with a penalty loading and carry-over points, might equate only to a one-game suspension. But if there was a charge of plain stupidity in the laws of the game, the Sydney spearhead would be facing a considerable spell on the sidelines indeed.

What on earth was going through, or more to the point, not going through Hall's head, when he flexed his considerable muscle at Wakelin?

Apparently the same lack of restraint that led to that now infamous strike on West Coast's Brent Staker at the same venue back in April, which cost Hall a seven-game suspension.

Some of us were as appalled at the hysterical reaction to that blow and calls for lifetime bans as by the sight of Staker's eyes rolling back in his head.

But if nothing else, that outcry should have taught Hall that he would subsequently be skating on very thin ice in the court of popular opinion, not to mention with the AFL Tribunal. And, more significantly still, with his coach and teammates.

It wasn't just the Wakelin incident that defined Hall's bad night out. It was the five free kicks he conceded, a quarter of Sydney's entire tally. The times Wakelin was able to run off him and become a springboard for Collingwood's attacks. And the generally poor body language of a player looking beaten and very, very frustrated.

As great a player for Sydney as he's been, the seeming inability to turn around a poor start is a considerable chink in Hall's armour.

Those days don't come nearly as frequently as they did during Hall's early years with St Kilda, but when they do, they're just as costly, most notably on grand final day 2006, when Hall's most ill-timed off day proved critical in a premiership lost by just one point.

The stakes on Saturday night weren't nearly so high, though the Swans would have just about sealed a top-four spot, putting 10 points between themselves and Adelaide, had they extended their winning streak to seven.

But Paul Roos clearly has an issue to deal with, one completely at odds with the culture that has helped make Sydney the success it has been these past five years.

The cornerstone of the Swans has been their superb team ethos and discipline, an example set by their most senior players. But a couple have this season let them down on that very front.

Hall's Saturday night stinker against the Magpies was as notable and damaging as was the absence of the suspended Adam Goodes, the result of his continued flirting with the laws regarding body contact.

Goodes rolled the dice once too often with his hit on Melbourne's Clint Bartram in Canberra a fortnight ago, having escaped being penalised for earlier contact with Port Adelaide's Matt Thomas and West Coast's Adam Selwood.

It was a couple of days after the Selwood incident that Roos said he'd counselled Goodes on appropriate contact. "He knows it's unacceptable and he needs to modify the way he does those sort of things," he said.

At the same press conference, Roos anticipated Hall's return the following Saturday. He said Hall's seven-game penalty was a "wake-up call" and that the key forward was looking forward to "rebuilding his reputation among his footy club".

Goodes overstepped the mark again less than two weeks after Roos' comments. And less than a month later, there'll be a fair bit more rebuilding for Hall to do should he fall foul of the match review panel again. Particularly, you'd think, with Roos.

Coaches simply can't afford players letting their personal frustrations impact on their team's fortunes. It's why Mick Malthouse, despite Collingwood's terrific win on Saturday, laboured the point about three 50-metre penalties conceded by an "inability to control emotions".

That same failure was present when Goodes cleaned up Selwood in Perth, the dual Brownlow medallist frustrated after being cleaned up himself at the first centre bounce. And the same frustration was implicit in Hall's stupidity on Saturday night.

Even Roos, a man whose demeanour remains unflappable no matter the extent of the problem, must be getting sick of these rushes of blood from his senior men, and the potential erosion of the very characteristic that has taken his Sydney outfit to the lofty heights it has reached.

At the moment, no one threatens the "Bloods" code more than their most talented couple of players.

Roos and his wife Tami are noted spiritualists, Tami herself having counselled some Sydney stars. And given the combustibility Hall demonstrated again on Saturday night, she might have a bit more important work to do before this season's through.