The AFL's crackdown on taunting an opponent was on full display in prime time on Thursday night when two players were penalised for rubbing an opponent's head during Fremantle's 38-point win over Sydney.
Fremantle defender Luke Ryan was the first culprit, condescendingly rubbing the head of Chad Warner after the star Sydney midfielder missed a snap set shot in the first quarter.
The umpire immediately paid a free kick against Ryan, handing Charlie Curnow a gift of a goal from the top of the goalsquare.
Then during a tense period in the third quarter when Fremantle had closed a 25-point deficit to 10 points, Sydney veteran Dane Rampe made the same huge gaffe when he rubbed Jye Amiss's head after the Dockers' spearhead had given away a free kick.
The free kick was reversed, with Rampe left breathing a sigh of relief when Amiss missed the set shot.
The AFL brought in the head-rubbing rule in time for round three after Fremantle spearhead Pat Voss had ruffled the hair of Melbourne defender Harrison Petty and taunted him with a 'cry-baby' gesture.
"It's clear. The AFL said it's clear. Maybe we could have educated our players a little bit better on that," Longmuir said of Thursday night's hair-rubbing free-kicks.
"I haven't seen it in the game for months, so for two to happen in one night is a bit odd.
"But the AFL has made it really clear that you can't do it. So why do it?"
Cox said the rule was crystal clear and players simply had to abide by it.
"You've got to adhere to it and be disciplined in the moment," Cox said.
"Don't let frustration change the outcome of what you should be doing. You should be focusing on what you can do next, not on trying to rub it in a little bit.
"The best teams don't do it. So we need to make sure that we're really disciplined in those moments."
Cox was disappointed one of his team's most senior leaders gave away the ill-disciplined free kick.
"There'll be slip-ups, but as coaches we are a bit firmer on our leaders than our kids, and so we should be," he said.
Sydney (13-4) conceded 100 points in the second half on the way to the 15.21 (111) to 10.13 (73) loss.
But one massive bright spot to come out of the game was a five-goal haul to Coleman Medal leader Curnow, who now has 50 goals for the season.
"He has a presence as soon as he walks into the club," Cox said.
"All year, he's been great for our footy club.
"He's built into the last couple of months to be a really strong focal point for our players, purely by the way he's competing to win, halve, or do whatever he has to do when the ball comes inside 50 or outside 50."
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