The Sydney Swans will head to Perth to face Fremantle this week with one of their most inexperienced line-ups in recent history, but coach John Longmire is excited by the prospect.

The Swans have played seven first-gamers this season, and last week's team that beat Carlton by six points at the SCG contained nine players with less than 30 games of senior football to their names.

Toby Nankervis is expected to replace the injured Callum Sinclair (knee) for the Dockers match, so Longmire's batch of raw youngsters could reach double figures on Sunday, with Nankervis (eight games) and Sam Naismith (four) to lead the Swans' ruck division.

With Sinclair and No.1 big man Kurt Tippett (hamstring tendon) both missing, Longmire has thrown his full support behind Naismith and Nankervis, and backed them to get the job done against Fremantle pair Jonathon Griffin and Zac Clarke.

"They've both played pretty good games for us this year, and to get another opportunity is a good thing for them," Longmire said.

"They're two young players who have showed promise and they'll get more exposure, like a lot of our younger players are getting at the moment.

"I think it's been a fantastic thing for the footy club.

"It's terrific that we've been able to keep evolving and players are getting opportunities, and grabbing those opportunities.

"It's not just about naming young players and getting games under their belt, they actually need to be competitive and playing well."

The Swans' trip west looks a tricky one despite the fact that nine wins and 13 spots separate the two sides on the ladder, with Fremantle sure to be inspired for their captain Matthew Pavlich, who plays an historic 350th game for the club.

The six-time club champion has kicked 24 goals from 14 games this year and has copped some criticism for his decision to continue his career for a 17th season, but Longmire said he had no doubt Pavlich made the right call to play on.

"Absolutely he should have, he's had a really good year," he said.

"He's been one of their better performing forwards.

"I can only go on what Ross Lyon has said publicly, and Ross knows his footy.

"He's said that Matty Pavlich has had a really good year, so I tend to take that on face value."

Longmire believes his young side will embrace the occasion and benefit greatly from the experience of playing in front of what should be a sold out Domain Stadium.

"We understand that there'll be a big crowd there," Longmire said.

"We know that the respect Matthew (Pavlich) has got throughout the competition is enormous, he's a revered figure in the west.

"We've had some big battles over there over the years and we've enjoyed it, and it's a fantastic opportunity for our younger players to be part of that.

"When you come up against a Ross Lyon-coached team you know what you're going to get, and that's a pretty competitive, disciplined outfit.

"I know what he's like as a coach, he's a fierce, fierce competitor, and he's so professional with his attitude.

"I've also had the pleasure of rooming with him and we had a few interesting interstate trips when we were scouting opposition teams.

"He's a fantastic coach and I really enjoy his company, but I'm sure we won't be enjoying each other's company this week."