Cats spearhead Cameron was held goalless as the visitors posted a 16.15 (111) to 10.8 (68) result in front of 37,565 fans at the SCG on Sunday.
Chris Scott's side should easily wrap up second spot for the finals with lowly Richmond up next for their final home-and-away clash. Ladder leaders Adelaide, who are one game clear, will also be heavily favoured to beat strugglers North Melbourne.
Cameron was looking to make strides towards becoming the first player since Lance Franklin in 2008 to reach 100 goals in a season.
Instead, Cameron - who leads the league on 79 goals - finished with just 10 touches and one behind.
Shannon Neale was electric early with four goals in the first half, while Tyson Stengle and Shaun Mannagh slotted three goals apiece.
Cats midfielder Bailey Smith collected 30 touches and five clearances.
Geelong coach Scott pulled all the right levers to limit Sydney's midfield stars, with Mark O'Connor brilliant in a tagging role on proven match-winner Isaac Heeney.
Heeney (one goal, 15 disposals) could not contain his frustration and gave away three free kicks to the Cats defender for high blows and a dangerous tackle.
Errol Gulden and Chad Warner had little say, while Pete Ladhams impressed (two goals, 35 hitouts) as a fill-in for concussed Swans ruck Brodie Grundy.
Sydney had started brightly and kept Geelong goalless until near the 20-minute mark of the first quarter.
But the Swans fumbled their 20-point lead, with Neale kicking two goals to fire the Cats ahead.
Ladhams responded to draw scores level at 4.3 (27) at quarter-time, with Cats ruck Mark Blicavs spraying his after-the-siren snap from the boundary.
A rare Tom McCartin goal helped the Swans regain the lead but it didn't last long.
Geelong wrestled back momentum with two Neale goals and built a nine-point lead at halftime when Stengle kicked his first major.
The home side just slotted one major in the third quarter before Tom Papley reached the 300-goal mark with a long bomb from just outside the 50m arc.
3°C