In Saturday's high-pressure clash at Norwood Oval, the tough-tackling Swans were wasteful but the better team, with the exceptional Heeney the difference in a 14.16 (100) to 9.14 (68) win.
Dean Cox's Sydney move to 4-1 and are on top of the ladder - after Hawthorn handed the Western Bulldogs their first loss of the season on Saturday night.
The Swans lead by percentage from the Dockers, Hawthorn and the Bulldogs, with all teams having four wins and one loss.
Heeney jagged two goals and 12 score involvements, along with 33 disposals, 538 metres gained, 10 clearances, 11 tackles and 18 contested possessions.
"I just can't ever question what he does on the football field," Cox said.
"His effort's phenomenal, his attention to detail, and he performs on the biggest stage as often as anyone does and that's why he's the player that he is.Â
"He was phenomenal again tonight, really tough and uncompromising.
"He leads from the front and drags people along with him, and also when you're trying to set standards and the way you want to play, he epitomises that better than any."
Heeney was delighted with the victory, and happy with the pressure he brought to the contest.
"It was nice to contribute for four quarters and have an impact and use the ball really well,'' Heeney told AAP after the match.
"I think my pressure was all right too, which was nice."
Heeney enjoyed stellar support from Chad Warner (two goals, 22 disposals) and Justin McInerney (26 disposals), while James Jordon blanketed Noah Anderson.
"I thought we were relentless on the opposition," Cox said.
Ruckman Brodie Grundy (20 disposals, 12 tackles, 36 hitouts, seven clearances) worked over Jarrod Witts and Mac Andrew.
Sydney spearhead Charlie Curnow kicked 0.4 and sent another shot out of bounds, but Tom Papley (three goals) and ex-Sun Malcolm Rosas Jnr (two) chipped in.
Sydney were dominant in the air, with Gold Coast failing to take a contested mark, compared with 10 by the Swans.
With Christian Petracca (hamstring) and Bailey Humphrey (suspension) sidelined until next week's clash with Essendon, Matt Rowell (32 disposals, nine clearances) and Suns defender Bodhi Uwland (26 disposals) were typically prolific.
Ben Long kicked three sensational goals, but Damien Hardwick's Suns slipped to 3-2.
"Contest-wise, they were just cleaner and clearer around the contest than us and they got away," Hardwick said.
"I think contested ball and tackle numbers paint a story.
"They're playing some really, really good footy and the fact of the matter is there's a gap between us and those sides at the moment."
Sydney's Callum Mills copped a knee to his lower back in the opening term, but played out the game.
The Swans led all game, but Max King's second goal brought the Suns within 10 points late in the third quarter, before Sydney kicked away for a Parade party.
Sydney return to action with their derby against GWS on Friday.
