SYDNEY Swans coach Paul Roos says star recruit Daniel Bradshaw remains on track to play against St Kilda in round one, even though he won't appear in a single practice match.

However, Roos said the former Brisbane Lions forward would not be risked if his recovery from a knee arthroscopy encountered any setbacks.

"He's run three times this week, he'll run again all next week and probably start training late in the following week," Roos said before training at Lakeside Oval on Thursday.

"He's on track to play, he's done everything that been asked but there's still three weeks to go yet. If there are any hiccups, he won’t play."

Roos was apparently unfazed by the prospect of heading into the season opener at ANZ Stadium with an untried forward structure.

"We haven't had [Bradshaw] before so it would be nice to have him in the team, but he's such an experienced player that it's not going to affect him as much," Roos said.

Instead, he said ruckmen Mark Seaby and Shane Mumford were likely to be played in attack alongside Jesse White in Saturday night's NAB Challenge clash against Essendon at Blacktown in a bid to acclimatise the team to having two big forwards.

While Bradshaw remains on the sidelines, the Swans will be bolstered by the return of co-captain Craig Bolton and Rhyce Shaw, who will have his first hit-out of the pre-season.

Young midfielder Dan Hannebery is also likely to see some game time against the Bombers.

Roos said he was looking forward to juggling all four of his running defenders - Shaw, Martin Mattner, Nick Malceski and Tadhg Kennelly - in the same team for the first time.

He hinted Mattner would push into the midfield and Malceski could spend time forward of centre, while Shaw's game time would be managed carefully.

Saturday's clash at Blacktown also marks the last chance for several fringe players to stake their claim for a round one berth, as the Swans will begin to trim their playing squad from next week.

"It starts to narrow it down to maybe 24, 25 players that we take to Narrandera [in week four]," Roos said.

"I'd suggest that apart from Braddy, if you’re not playing next week, it will be pretty hard to get a game in round one."

Roos said the prospect of leaving in-form players out of the team to face the Saints was a pleasant contrast to 2010, when a shortened list and a spate of injuries forced the club to pick out-of-form players.

"The good thing is that there are a lot of players putting their hand up for selection and there will be some good players who won't play," he said.

"There will be some players that mightn't play in round one who will still have a significant role to play throughout the season. There will be some young players that will probably just miss out who will certainly play during the season as well.

"Obviously we know a number of them who will be there but there are still quite a few spots up for grabs."