THE Sydney Swans will retain their two premiership points, but were fined $50,000 - $25,00 suspended - last night after an AFL investigation into the botched interchange that saw them field an extra man during the dramatic final moments of Sunday's draw against North Melbourne.

The AFL accepted the Swans' submission that it had been the over-exuberance of 19-year-old debutant Jesse White in running on to the ground before ruckman Darren Jolly had left the field, rather than Jolly's hesitancy in leaving, that resulted in them having 19 men for about 18 seconds near the end of the quarter.

The investigation was launched on Monday after the discrepancy had been noted by a North Melbourne interchange official. The fact Jolly had helped launch the attack that led to Brett Kirk tying point with 66 seconds left on the clock had led to speculation the Swans might lose their premiership points.

Jolly's handball began a chain that led to Kirk's snap shot that was controversially deemed to have been touched on the line by North defender Michael Firrito. However, the Swans argued in a written submission that White, rather than Jolly, should be considered the "extra man" because in a moment of confusion near the interchange area he ran onto the ground before he was meant to. Although their explanation was accepted and they kept the valuable two points, the fine was more than triple that handed to the Western Bulldogs in 2006 and Hawthorn during the pre-season competition for similar offences. Both clubs were docked $7500 for their troubles.

AFL football operations manager Adrian Anderson said the size of the fine reflected the seriousness of the offence.

"It is incumbent on clubs to ensure that they do not breach the laws of the game and it is entirely their responsibility to ensure their interchanges are made correctly," he said.

Swans coach Paul Roos said the club would accept the finding.

"We were confident that Jesse didn't have any influence on the play and the investigation was handled well from all sides, so I think we'll move on," Roos said.

The Swans submitted that White had been standing with teammate Kieren Jack, while North pair Brent Harvey and David Hale were also waiting to come on. Harvey and Hale replaced teammates and Jack followed his opponent for the day, Harvey, replacing Lewis Roberts-Thomson. But in his confusion White, a Queenslander who had a basketball background before being converted to AFL, also ran onto the ground rather than waiting for Jolly to leave.

While Jolly played a part in Kirk's tying point, the Swans claimed they were inconvenienced by White's early entry because he wrongly ran into defence, believing he should take Roberts-Thomson's place rather than run to Jolly's opponent, Hamish McIntosh. Left unattended after Jolly finally answered the screams of the Swans' officials to come off, McIntosh marked the kick-in from the tying point and launched the Roos' final attack.

Anderson yesterday interviewed the emergency umpire, interchange steward and North Melbourne officials before reaching his finding.

He said the fact the "the extra player on the field did not go near where the play was taking place and involve himself in the contest for the ball; both clubs were of the view the mistake was inadvertent; the Swans immediately acted to remove the closest player once they realised they had an extra player on the field; [and] North Melbourne had the ability, but chose not to call for a [head] count, pursuant to the laws of the game," had all been factors in the decision.

The Kangaroos took a conciliatory stance on the issue, saying that they believed the extra man was inadvertent and had no influence on the result, rather than pushing for the matter to go to the AFL Commission, where a tougher sanction might have applied.

¡ Signage on the fence and the railings on the retractable seats at ANZ Stadium will be padded following an AFL investigation into how Barry Hall broke his wrist while running into the fence during the tumultuous match against West Coast two weeks ago.