Sydney have affirmed themselves as AFL premiership favourites with a Lance Franklin-inspired four-point win over ladder leaders Port Adelaide.

Franklin nailed five goals in the second half to lift the Swans to the 14.14 (98) to 13.16 (94) victory on Saturday in front of a near-capacity SCG crowd of 41,317.

The triumph extended their unbeaten run to eight and has them within just one game of their in-form rivals.

Billed as the biggest match of the season so far, fans did not leave disappointed.

While both struggled on a seemingly slippery deck and often wasteful in front of goal, never were they separated by more than 21 points.

A late-blooming Franklin, without his forward buddy Kurt Tippett, proved the difference, his five-from-five haul making up for a goalless first half and proving too much for a resurgant Port outfit who came to within a point in the final quarter.

Co-captain Kieren Jack opened the home side’s account in the tit-for-tat contest, marking his 150th senior game with a goal in the opening 90 seconds.

Jarrad McVeigh followed it with one of his own moments later, as Port struggled to keep an early handle on a rampant Swans outfit.

The pressure was all on the visitors, kept scoreless until an 18th-minute free-kick to Jay Schulz provided some relief.

While the Swans eked out to a 12-point advantage into the first break, the momentum shifted the Power’s way in the second term – Angus Monfries and Matt White leading the way with two goals each to snatch the lead for the first – and only – time after just under an hour of play.

But the at-times silent crowd lifted after the Swans hit back with a spectacular 60m mark and kick from speedster Lewis Jetta and a trio of goals to dual Brownlow medallist Adam Goodes to go into halftime 6.12 (48) to 6.5 (41).

McVeigh continued the run with a major, moments into the second half, backed up by successful boots from fellow All Australian midfielders Josh Kennedy and Dan Hannebery.

Franklin, outnumbered for most of the match, went on to give fans more to cheer about – ending a near 90-minute spell without a major with two quickfire majors in less than 90 seconds.

Port Adelaide star Chad Wingard returned fire with his first of the afternoon to narrow the gap to only 15 points just before heading into the last break.

It turned into a one-point contest in an entertaining final term, with a goal to Monfries and Schultz putting the Power back into the mix – only for Franklin to ruin it with his late bounce-back.

Port midfielder Hamish Hamlett was subbed off in the third quarter with an apparent ankle injury.

Swans big man Mike Pyke was a late withdrawal from the game, replaced by speedster Gary Rohan who came on for Brandon Jack early in the final quarter.

AAP