POWER big man Daniel Stewart believes there's still a spot for him in Port Adelaide's best 22, despite the intense challenge he faces to play in the ruck or in the forward line this year.

With Jarrad Redden's NAB Cup potentially positioning him as the Power's No.1 ruckman - and with Brent Renouf now back in action - Stewart said competition in that department was fierce.

But he said there was no certainty of selection in the forward line either, with Justin Westhoff, John Butcher and Jay Schulz all performing well so far.

"We've got Schulz up and going and Butch kicked five last week and Westie had a rest today but he's going really well," he said after last Saturday's win over Fremantle.

"I'd hate to be a coach at the moment."

In his third AFL season since being drafted with pick No. 82 in the 2009 NAB AFL Draft, Stewart agreed that season 2012 needed to become a "break out" year.

Having become a potent player in the SANFL, he said it's time he took his game to another level.

"I'll be looking to try and cement my spot in the team," he said.

"I had a full pre-season, didn't miss a training session. It's probably time for me to step it up and prove that I'm meant to be playing AFL."

He said he still believed the Power could play three tall forwards in 2012, not counting the two ruckman.

"Geelong last year had two ruckmen and then three talls down in the forward line, so they showed that it worked as well," he said.

"(Nobody) could say that it can't work."

While Redden has clearly been the side's best ruckman in the NAB Cup, Stewart said the injury setbacks for both Renouf and Matthew Lobbe have allowed him to prove his worth and versatility.

"With Renouf not having a full preseason and 'Lobbes' getting injured, obviously I can come in fill that ruck spot for a bit," he said.

"But I'm sure 'Lobbes' will be back up in a few weeks and he'll be right up there.

"I think it's really helped with Shaun Rehn coming into the side and helping out our ruck stocks. It's really helped my ruck situation."

The Power take on Melbourne at AAMI Stadium on Friday night - their last pre-season match before they tackle St Kilda in round one of the premiership season.

Stewart said the game was important for the club to put finishing touches on their structure and to settle on a side to face the Saints on April 1.

Harry Thring covers Port Adelaide news for AFL.com.au. Follow him on Twitter: @AFL_Harry.

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