Sydney chairman Richard Colless says a bumper AFL crowd for Friday night's AFL preliminary final won't change the fact that the Swans still rely on success to stay viable in a rugby league-dominated city.

Colless says hosting Australia's biggest sporting club in the country's biggest city, in a final on a Friday night at ANZ Stadium is a promoter's Heaven.

There is some chance it will attract the biggest crowd ever for an AFL finals match outside Victoria, which is currently the 71,019 that watched the Swans fall to Brisbane at the same venue in 2003.

But Colless dismissed billing of the fixture as the latest skirmish in a code war and has no interest in how the crowd compares to that for the Canterbury-South Sydney NRL blockbuster at the same venue a night later.

"This is a rugby league town and if one day in the year we get more than they do to a game, big deal," Colless told AAP on Thursday.

"I think you measure it in column centimetres, you measure it in talkback radio, you measure it in pay-per-view games.

"(Rugby league) just dominates, it's the dominant winter sport by a mile.

"We want substantial crowds, but whether they're bigger or smaller than the NRL is kind of irrelevant."

Colless says reaching this point in the finals has clearly increased the Swans' exposure and that will grow further if they reach the grand final.

But the flipside is support could shrink fast if the Swans' remarkable record of making finals in 14 of the past 17 years gives way to a slump.

"We don't have the luxury of a massive supporter base," Colless said.

"Richmond's a good example - they've had so little success, two finals campaigns in 30 years, they still draw massive crowds.

"We don't have that luxury, we are somewhat a hostage to how we go on the field."

But Colless said such considerations have taken a backseat with the Swans potentially two wins from a premiership.

"The reason we play this bloody game is to win," he said.

"Apart from putting bums on seats and money through the turnstiles we want to win it."