HAWTHORN coach Alastair Clarkson says getting valuable match time into some returning stars will be among the biggest positives from tomorrow's clash with Port Adelaide.

While gaining four premiership points is the number one priority, the Hawks mentor was thinking of the bigger picture as he welcomes back several key players for the round-four clash with the Power.

Ruckman Robbie Campbell and Simon Taylor return to the line-up, while rugged midfielders Brad Sewell and Jordan Lewis will add grunt to the Hawks on-ball brigade.

"We feel that those four players, they're all pretty critical to our whole structure through the midfield," Clarkson said from Waverley on Friday.

"Whilst that's going to help our midfield a little bit, our defensive end now is a little bit riddled, but to have those four guys back [is great].

"We're hopeful that they'll all make a really solid contribution this week but it's actually getting them back into the fold and getting them match conditioned again for what they can contribute through the middle of the season and the latter half of the season that's going to be really important for us."

As Clarkson suggested, it hasn't all been good news this week for the reigning premiers.

The Hawks' injury battle continues, with the club this week losing defenders Grant Birchall (thumb), Xavier Ellis (foot) and Stephen Gilham (knee).

While Birchall and Ellis copped injuries in last week's clash against North Melbourne, it wasn't until this week that a recurrence of Gilham's knee injury became apparent.

Clarkson said the Hawks were hopeful swelling on his left knee would only prove to be a minor setback.

"He's going to be a pretty heavy loss for our back six, but you know we've been able to cover in that area of the ground before and we'll just have to do so again," he said.

"He's had only five days to the minute of recovery from that game, so he's still got a bit of swelling and hopefully that'll dissipate altogether across the weekend and he'll be available pretty soon.

"But with knees they're tricky things, you've just got to wait and allow them to settle before you can put the full load through them."

Gilham's absence is likely to mean big man Campbell will spend some time in defence as the Hawks try to come to grips with the unpredictable yet dangerous Port Adelaide attack.

"I do say at different stages of the game Robbie will have to play in the back half for us, but we've got our three tall guys in terms of rucks and we haven't had that for a long period of time, certainly not this year," Clarkson said.

"So that's pleasing that our ruck stocks are back up where they've been in the past."

Sewell, who has missed the past two matches with a groin strain, and Lewis – yet to play in 2009 as he returns from a shoulder injury – are likely to spend prolonged periods on the bench as the coach eases them back into action.

Meanwhile, Clarkson said Trent Croad had recovered well from his most recent surgery and was still on track to resume playing in the second half of the season.

"He's just about on the verge of running again and he'll more or less do a mini pre-season over the course of the next eight to 10 weeks," he said.