BRISBANE has started its premiership defence with a four-point defeat against Sydney, a come-from-behind victory over last year's runner-up at the SCG.

The Lions were forced to bravely chase down the hosts on this occasion, and then hold on desperately for a 12.14 (86) to 12.10 (82) triumph on Saturday.

The Swans were left to rue a missed late opportunity to take a critical first step on their road to redemption, after Isaac Heeney booted a goal with two minutes remaining then Chad Warner surged away from the next centre bounce.

When the ball spilled to Braeden Campbell the Swans forward launched a 50m snap on his preferred left boot but the ball sailed narrowly wide and short of the goal line for a rushed behind to allow the Lions to hang on.

But the first-start win was marred by another head knock for Brandon Starcevich late in the final quarter, the defender's third concussion from his past 12 outings.

Starcevich, who suffered his last concussion just last month in a pre-season game, was helped off the field following the accidental clash of heads with Sydney's Justin McInerney.

The Swans made a fast start and led by as much as 23 points in the opening term but paid the price for failing to make the most of their opportunities as the Lions gradually wrested back the momentum.

The Lions began the post-Joe Daniher era searching for goalkicking threats and it was Zac Bailey that stepped up to spark a resurgence and then break the game open with four goals.

Josh Dunkley was immense in the Lions' midfield with an equal game-high 27 disposals and 10 tackles and added a late goal that looked to have sealed the game after a horror kick from Matt Roberts running out of the Swans' defence.

If you're only as good as your last game then Lions young gun Will Ashcroft is clearly very, very good and last year's Norm Smith medallist again showed his class with 21 disposals, but was arguably outshone by younger brother Levi who gathered 25 in a hugely promising debut.

It was little surprise to see James Jordon go straight to Lachie Neale as the Swans' midfield minder restricted the dual Brownlow medallist to only 10 disposals. 

But when Bailey sparked the Lions' comeback with three goals either side of the main break the Swans found it difficult to take back control.

Heeney battled hard in the midfield and later as a deep target in attack to finish with 23 disposals and two goals, while Nick Blakey helped get the Swans up and running with his dash and dare while gathering 23 touches.

The Lions dismantled the Swans in last year's decider in part by picking through their zone defence with 145-81 uncontested marks but the hosts set out to avoid being beaten by what they know.

With a noticeable lift in intensity and better man-marking around the field, the Swans stifled the Lions' ball movement and limited the visitors to only 58 uncontested marks while taking 72 of their own. 

The Swans were unable to keep pace with the Lions when the game was at its hottest with a 0-2 start to their first season under new coach Dean Cox. 

Warner brothers earn mixed reviews
Chad Warner reminded the Swans why he has become one of the hottest players in the competition with a bursting run away from a centre bounce to boot a long-range goal in the second term. But that was one of few highlights on a relatively quiet day for the older of the Warner brothers as he was restricted to 20 disposals. Corey Warner took his chance to instead step into the spotlight with a pair of goals both helped by 50m penalties in the opening term then was a useful addition to the Swans' forward half to finish with 15 touches. Chad undeniably remains the star of the Swans show, and added a second goal late, but Corey might just be ready to edge out of his brother's shadow.

Sons of a gun make most of late scratching
Brisbane coach Chris Fagan had earmarked Levi Ashcroft to debut as the substitute but was soon forced to unleash the prized father-son selection from the first bounce after the late withdrawal of Charlie Cameron. Ashcroft made the most of his opportunity to join the action from the early exchanges as he gathered five polished disposals in the opening term. The 18-year-old looked comfortable playing alongside older brother Will as the Norm Smith medallist went to work on the inside with 21 disposals and eight clearances, while Levi was full of promise on the outside with 25 touches and 495m gained.

Campbell stakes claim for starting spot
Braeden Campbell began six matches as the substitute last season including the decider against Brisbane but is now pressing his claims to be a regular in the starting 22. Campbell arrived at Sydney with a reputation as a long-kicking defender but has since settled into the forward half. The 23-year-old remains one of the classiest kicks in the competition, let alone just at the Swans, but has added intense pressure to his game since spending more time in attack. Campbell booted the opener with a clever left-foot snap and again set the tone for the Swans with a chase-down tackle on Noah Answerth that he finished with a goal as the smooth-mover tightens his grip on a place in the side.

SYDNEY         4.0     7.3     9.6     12.10 (86)
BRISBANE     1.3     4.8     10.10     12.14 (82)

GOALS
Sydney: Co.Warner 2, Campbell 2, Ch.Warner 2, Heeney 2, Lloyd, McCartin, Hanily, Hayward
Brisbane: Bailey 4, Zorko 2, Fort, Ah Chee, McInerney, Hipwood, Morris, Dunkley

BEST
Sydney: Heeney, Blakey, Rampe, Grundy, Rowbottom, McInerney
Brisbane: Bailey, Dunkley, L.Ashcroft, Zorko, Berry, W.Ashcroft, Wilmot

INJURIES 
Sydney: Nil
Brisbane: Lohmann (ankle), Starcevich (concussion)

LATE CHANGES
Sydney: Nil
Brisbane: Charlie Cameron (calf tightness) replaced in the selected side by Conor McKenna

SUBSTITUTES
Sydney: Riley Bice (replaced Ben Paton in the third quarter)
Brisbane: Conor McKenna (replaced Kai Lohmann in the first quarter)

Crowd: 34,906 at the SCG