Sydney's second-half numbers were dire and it showed on the scoreboard in the team’s disappointing 22-point loss to Melbourne at the SCG on Thursday night.

The Swans dominated all the key areas in the first term without capitalising in front of goal, and it came back to hurt them when they faded badly after half-time.

The home side led the inside 50s (35-22) and contested possessions (78-67), plus the clearances (24-17), despite the heavy influence of Melbourne star Max Gawn in the ruck.

But just as they'd held sway in those key areas before the long break, they fell away just as badly in the second half.

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The Demons piled on 37 inside 50s to 17, won the clearances easily (27-13), and monstered the Swans in contested ball (86-55).

Sydney coach John Longmire said it was no surprise the Dees kicked 7.6 to 3.2 after half-time to hand his side it's third loss of the year.

"In the second half we got smacked around the ball," he said post-match.

"We were minus 30 in ground balls, they doubled us in the clearances, and we weren't able to shift the momentum back.

"It's pretty hard to win a game of footy when you play for 65 minutes.

"We played some good footy early, but you need to do it longer than that and stick it out against a good opposition, or any opposition really.

"The opposition are always going to get a run on, but we couldn't arrest the momentum.

"They got their tails up and were able to run onto it, they were clearly proactive around the ball and we found it hard to stop.

"We've got to be better than that, we understand Gawn was well on top in the ruck, but we've still got to make sure we stop them better than that."

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While the Swans' forward line failed to capitalise on the team's dominance early, the way the footy came inside 50 made it extremely difficult at times for tall targets Lance Franklin, Sam Reid and Nick Blakey.

Longmire said the decision-making of his players through the middle of the ground against the Demons was an area of concern.

"We talked about that during the course of the game a number of times, we went a bit shallow (kicking the ball inside 50)," he said.

"We kicked it to centre-half-forward and they were able to turn it over.

"You've got to be really mindful if you kick it there, it's a dangerous spot and we kept kicking it there.

"We just didn't use the footy well in that front third."