SWANS coach Paul Roos is set to inject some run into his injury-hit side to play the Bulldogs with midfielder Jared Crouch poised to return and hard-running Ryan Brabazon a strong possibility to make his debut.

The Swans go into the match without Brownlow Medallist Adam Goodes (groin pain) and ex-Cat Henry Playfair (hamstring) while key defender Nick Malceski (calf) is also under a cloud after being a late withdrawal for the last three weeks.

"It's an important game from a selection point of view to get some fit players in the team and get some real run back. I think we've lacked some run," Roos said on Friday.

Jared Crouch, 30, returns to the seniors after playing four games in the reserves following a long lay-off with recurring hamstring problems.

In fact, he could get a tagging job on Jason Akermanis, who has previously referred to Crouch as a "pest" for his tight tagging jobs on the star onballer.

Nick Malceski and fellow backman Leo Barry both trained on Friday and could play and 21-year-old Brabazon could be named for his first game.

"Watching Jared (Crouch) train the other night, he looked like the Crouchy of a couple of years ago. He hasn't played senior footy for a while so we're not too sure how he'll go but at least he comes in really fit.

"Ryan (Brabazon) is another midfielder who is a really good runner. So we're preparing for a team that runs well and can rotate their players in the middle of the ground. With possibly Ryan and Crouchy coming in, that gives us two very fit players who can hopefully play on their quality midfielders and small forwards," Roos said.

Brabazon has been on the cusp of senior selection for a couple of seasons, has worked hard on building his strength and fitness in the reserves, and looks set to make the breakthrough.

"Ryan is a kid who's played a fair bit of footy. He's a bit more mature and he won't be overawed. He's an elite runner, so (he’s suited to) a role through the midfield matching up on some of their quality midfielders to give us some run."

Quizzed on whether the Swans can match the mobile Dogs in their running, Roos said that was probably the main question mark over his side prior to the contest.

He also noted that when two players down last week against the Crows, the Swans lifted its intensity. They were able to run with the Blues in the second half a week earlier.

"It's probably a bit of a mindset at the moment but it's also about putting out a side that can compete the way we want to compete and run out games,” Roos said.

"If we don't do that within the first five to ten minutes, we'll know and we'll get blown off the park."