SYDNEY coach Paul Roos has branded the AFL's updated interchange procedures as "ridiculous", "embarrassing" and a blight on the game.

The over-officious new system — introduced post-haste after the Swans were found to have had a 19th man on the field during their match against North Melbourne three weeks ago — had proved a significant hindrance to coaches in the trial run, Roos said.

After his side defeated Essendon by 91 points yesterday at ANZ Stadium, Roos said he was not opposed to teams being penalised for having extra men on the ground, but complained about the AFL's insistence that players' names had to be announced to officials before they were permitted to take the field.

"I think it's a bit embarrassing when you watch games on the weekend and you see five on the interchange bench and six on the interchange bench … I think that's just as embarrassing as having 19 versus 18, to be honest," Roos said.

"In simplistic terms, all we're trying to achieve is 18 versus 18, nothing more, nothing less. So why the hell it's so complicated is completely beyond me.

"I think the free kick's fine, I think they've sorted that out … but I think it's ridiculous you have to go through so much protocol to get players on and off the ground.

"It's the only game I know in the world where you've actually got to hand over a bit of paper before you're actually allowed on the playing surface. I don't know, it just seems ridiculous to me, but obviously I don't run the AFL."

Roos estimated that both sides would have had fewer than 18 players on the field as many as 20 times yesterday.

"I think it just looks ridiculous for the game that we've actually got that situation and I don't understand why we have to have paperwork. No one's been able to explain it to me yet."

In a break from convention — albeit his unconventional one — Roos sat in the coach's box yesterday, while his most senior assistant, John Longmire, watched the game from the bench. The Swans employed former club captain Stuart Maxfield to help a team manager, John Payne, run the new interchange procedures.

Nick Malceski made a successful return from injury, only 86 days after having revolutionary surgery to repair the ruptured anterior cruciate in his left knee.

But in a big blow, Tadhg Kennelly dislocated his right knee in a tackle during the second quarter.

Kennelly missed nine games last year with a knee complaint and will be fully diagnosed after scans today.

"It's a similar thing he did last year … but at this stage, it doesn't look anywhere near as bad as last time," Roos said.

Malceski finished in high spirits after playing about 73 minutes. He finished with 10 touches and was used in attack and defence but looked a touch tentative at times.

"Until the end of the year, we're not across the line, but everyone saw today the operation itself has been a success, the rehab's been a success and hopefully he can keep going for the rest of the year," Roos said.

"He's pulled up really well, he was really happy with the way he felt out there."

After a third straight loss by more than 10 goals — and the Bombers' second-heaviest of the season — Essendon coach Matthew Knights said his younger bodied players had been "pushed around" by the Swans after the midway point of the third quarter.

But with matches against Richmond (home), Adelaide (away) and Hawthorn (home), Knights denied the club's spirit had been damaged, despite Sydney kicking 13 unanswered goals before the completion of the match.

"We think we should improve from this point," Knights said.

"When you think we had Dustin (Fletcher), Mark McVeigh, Sam Lonergan come back into the team today, Jason Winderlich and Scott Lucas is on the horizon in coming weeks and also Adam McPhee and (Nathan) Lovett-Murray back next week from suspension, I would have thought we would improve our performance."

Key forward Lucas, he said, could return from his posterior cruciate ligament injury in two weeks.

What they said

Leigh Matthews (Brisbane Lions): "It seems to be a very complicated system to get a very simple end result, of making sure you've only got 18 at any one time."

Terry Wallace (Richmond): "What we've actually put in place has the potential to have much more impact on the game than the system that was in place."

Guy McKenna (Collingwood assistant): "I just don't think we have to process the numbers. I can't see any reason why that has to occur — one bloke comes off, one goes on; does it matter what number and who it is?"