ST KILDA vice-captain Lenny Hayes has backed Justin Koschitzke to make an immediate impact on his return from suspension.

Koschitzke was banned for three weeks following his head-high hit on Swan Nick Malceski in round one, but will be recalled to help fill the void left by injured skipper Nick Riewoldt against Port Adelaide this Saturday.

"We're obviously crying out for a tall target down there. We tried a few different things last week, and a few worked, but Kosi's a great player for us," Hayes said from Linen House Oval on Wednesday morning.

"I think every time he's been there, and Rooey (Riewoldt) has been out with injury, he's really taken that role on and played really well for us.

"I think he's pretty excited to get out there this weekend."

Riewoldt underwent surgery to his right hamstring tendon early last week and is expected to be sidelined for three to four months.

He has started a rehabilitation program after spending a week resting, and Hayes reported the captain's imposing presence still loomed large at Moorabbin.

"He's been really upbeat around the club and has been getting around all the boys - we don't expect anything less from the skipper," he said.

"He's still had a major impact around the place.

"He's going really well [with his rehab]. He's obviously a very focused individual and he's going to do everything he can to get back as soon as possible.

"I think anything that's going to help his recovery, he's going to try. He's been out to the hyperbaric chamber and is doing everything he possibly can."

The Saints remain unbeaten despite the loss of their champion forward, which Hayes attributed to a strong work ethic across the board.

"I think everyone's just playing their role. I think that's been the real strength of our team over the last year and a bit," he said.

"We haven't expected anyone to do anything spectacular - everyone has just sort of played their part. Guys like BJ (Brendon Goddard) and Milney (Stephen Milne) kicked big bags on the weekend but I think everyone has stuck really tight [to their roles].

"They've really taken it upon themselves to do their bit and that's where we've had success."

Despite a round-four thrashing from Geelong, Hayes expects a strong showing from the Power on a weekend where all teams pay tribute to the Anzacs.

"I know that as a club we make a pretty big focus about it," he said.

"It's a great round of footy and I know every team places a big importance on the Anzac Day spirit and playing the game in the spirit that they want the game to be played in.

"It would be great to be involved [in the public holiday blockbuster], but I think Collingwood and Essendon have got the right to it at the moment."