Sydney will look back on its failure to capitalise on a dominant opening term against Port Adelaide after falling to the Power at the SCG for the second season in a row.

The Swans had winners all over the ground and led all the major statistical areas in the first quarter, but despite the lopsided numbers – they won the inside 50 count 20-7, the clearances 15-6, and contested possessions 50-33 – the home side kicked just two goals to Port's one.

They maintained their advantage on the scoreboard by 14 points going into the second half, but with Charlie Dixon influential in the ruck and Ollie Wines having an impact around stoppages, their forward line looked dangerous.

Just as the Swans had done in the first term, Port won the inside 50 count 20-7, but they managed to turn it into scoreboard pressure with a seven-goal quarter.

The Swans came again but Port steadied to kick the last three goals of the match and seal the 23-point victory.

Swans coach John Longmire said his team paid the price for their wastefulness in the first two quarters.

"When you are on top and you have some momentum, you've got to make sure you convert a bit more," he said.

"Teams are going to get momentum in certain parts of the game and that happens, and you need to be able to be further in front, like we should have been at half-time.

"But also in the last quarter we got back (to within four points) and couldn't continue on."

Dixon finished the night with 17 possessions and 32 hit-outs, and combined well with Justin Westhoff in the absence of Port's number one ruckman Paddy Ryder.

"Dixon was pretty good when he went on the ball, they got their hands on it first around the stoppages and got the ball inside their 50, and the game turned," Longmire said.

"Towers was rucking (as well) but Dixon made a difference in that third quarter."

The Swans' experienced defence had an unusually off night, with a number of uncharacteristic mistakes handing the Power some important goals.

"They pressured pretty well absolutely, and they were good with their tackles inside their forward 50, but we made some basic errors," Longmire said.

Sydney midfielder Dan Hannebery could be in doubt for next week's derby against Greater Western Sydney after he copped a knock to the knee in the dying minutes of the match.

Longmire said the star onballer will be monitored over the next couple of days.

The coach is hopeful midfielder Zak Jones (calf) could be a chance to play the Giants after he was a late withdrawal against the Power, with tall forward Sam Reid (hamstring) is also in line to return at the SCG on Saturday night if he can get through training this week.