Sydney have tightened their grasp on a top-eight spot with a 51-point thumping of fellow finals contenders St Kilda at the SCG.
It was a powerful display from the Swans, who dominated much of Saturday's contest without proper reward on the scoreboard until they slammed five unanswered goals in the third term to set up the convincing 12.11 (83) to 4.8 (32) triumph.
The Swans outplayed the lacklustre Saints and restricted them to only two majors until the visitors added two consolation goals late in the final term.
The Saints struggled to regularly move the ball forward with enough speed or fluency and ended with their lowest score since 1957.
While the win lifts the Swans to a 9-5 record, the Saints slumped to their third consecutive loss since the bye and tumbled out of the top eight for the first time since round three.
With up to 12 teams now fighting for a finals place, the Saints' loss is potentially damaging ahead of three matches against fellow contenders.
Jake Lloyd (39 disposals), Nick Blakey (31, 560m gained), Oliver Florent (27, one goal) and Callum Mills (24) added polish to the Swans performance while Isaac Heeney booted three majors and Tom Papley two.
"I thought our back six or back seven were really good. They defended really well and to keep them to two goals until about 10 minutes to go was outstanding," Swans coach John Longmire said.
"They also gave us plenty of bounce and we just had a good mix tonight, of blokes playing their roles offensively and defensively."
Fringe midfielder Ryan Clarke performed a crucial role for the Swans in his first minutes of the season after being the unused sub twice, paying close attention to the Saints' in-form half-back Jack Sinclair.
Clarke booted two first-half goals but had even more influence for restricting Sinclair to only a season-low 17 disposals, well below the 28 he had averaged this season, and helping limit the Saints run and carry out of defence.
Dylan Stephens was another unheralded Swan to have an impact, the No.5 pick from the 2019 draft selected for his first match since round three and gathering a career-high 23 disposals.
"It's a sign of [Sinclair] going pretty well. When teams come to you, they respect you, they acknowledge what you've done, so that's good for him," coach Brett Ratten said about the Saints' defender.
"But sometimes if they sit on you, it's not about you getting the ball, it's about what you can do for the team, and we'll chat about that."
Saints skipper Jack Steele battled hard in his first match since injuring a shoulder in round nine to collect 27 disposals, while Sebastian Ross (31) and Rowan Marshall (23 touches, 39 hitouts) also contributed but were short on support.
Max King had an unusually quiet night, failing to kick a goal for the first time since round 11 last year.
The Saints have now lost their past seven matches against the Swans at the SCG, a streak that goes back to 2009.
They will need to bounce back quickly in what could be a season-defining month against other finals contenders with a match against Carlton on Friday night while the Swans face Essendon at the MCG the following day.
Australian Associated Press
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