St Kilda has survived a major scare to extend its unbeaten run to 18 matches with a one-point come-from-behind victory over a spirited Sydney at the SCG on Saturday night.

Having trailed for most of the second half the Swans took a one-point lead late in the final term when Jesse White kicked his third major of an epic contest, before Brendon Goddard levelled the scores with less than two minutes on the clock.

Leigh Montagna (34 possessions) capped a brilliant performance in the final seconds, snatching the win with a point after swooping on the loose ball to seal a 13.16 (94) to 13.15 (93) triumph.

A dominant third quarter saw the Saints take a 19-point lead into the final term having trailed by seven at the long break, but the Swans weren't done kicking the first two majors of the final term to close within a kick.

Nick Dal Santo (28 possessions) answered for the visitors before Michael O'Loughlin replied to whip the 27,805-strong crowd into a frenzy.

The Saints looked home when Andrew McQualter booted his second of the contest before quick-fire goals to Luke Ablett and White put the Swans ahead.

But it wasn't to be for the Swans who must now win their remaining four matches of the season to have any hope of a seventh consecutive finals appearance.

The Saints got the better of a fast and furious opening 15 minutes kicking the first two majors of the contest.

But it was anything but one-way traffic for the competition leaders as the hosts cut the deficit to six points at the first change when Adam Goodes kicked his first major of the night after the siren.

Sydney reclaimed the lead four minutes in only to concede the softest of goals to ruckman Steven King.

A titanic struggle ensued before the Swans, who looked the more committed team in a high quality second term, kicked clear with late goals to Martin Mattner and Ablett to lead by seven at the main break.

The Saints showed why they are yet to taste defeat this season kicking four unanswered goals in the third quarter to open up a 19-point advantage at the final break.

Sydney simply had no answer after relinquishing their lead eight minutes in through goals to Adam Schneider and Nick Riewoldt.

But they would save their best for last before falling agonisingly short in a pulsating final term.

St Kilda faces a nervous wait during the week after Stephen Milne was placed on report for striking Jared Crouch, who restricted the Saints star to just 10 possessions for the match, early in the opening term.

SYDNEY: 3.4, 8.9, 8.12, 13.15 (93)
ST KILDA: 4.4, 7.8, 11.13, 13.16 (94)

GOALS: Sydney: White 3, Goodes 2, Ablett 2, Bird, Barlow, Jack, Mattner, McVeigh, O'Loughlin,
St Kilda: Riewoldt 2, Schneider 2, McQualter 2, Gwilt, McEvoy, Milne, King, Gram, Koschitzke, Dal Santo,
BEST: Sydney: McVeigh, Jack, O'Keefe, Crouch, Bird,
St Kilda: Montagna, Goddard, Dal Santo, Schneider, McQualter,
INJURIES: Sydney: Craig Bird (shoulder) and Ryan O'Keefe (ribs) were forced to sit out most of the fourth quarter while Darren Jolly (hamstring) was repeatedly forced from the ground in the second half.
St Kilda: Steven King suffered a 'popped' right shoulder early in the second half but returned to the action in the final term.
REPORTS: Stephen Milne was placed on report for striking Jared Crouch in the first quarter.
CHANGES: Nil
UMPIRES: Donlon, Wenn, Findlay,
CROWD: 27,805 at the SCG