EAGLES assistant coach Darren Harris is looking forward to seeing his young defenders tackle Nick Riewoldt on Saturday, but doesn’t believe it's the last chance for other more experienced players.

Mark Seaby and Steven Armstrong get another opportunity  in the side to take on St Kilda at Subiaco Oval, while Matthew Spangher, Beau Wilkes and Eric MacKenzie will all get a crack at the superbly in-form Riewoldt.

"No doubt we believe he (Riewoldt) is their centre of gravity and his form has been outstanding," Harris said on Friday.

"Part of our planning surrounds him, but it's a great opportunity for Wilkes, MacKenzie and Spangher to get some great experience playing on a quality forward. Spangher comes in because his last two weeks (for East Fremantle) have been outstanding, so he's forced his way in based on that."

Seaby returns after playing the last seven games in the WAFL for West Perth and Harris doesn't believe his future at the club is in jeopardy, while Armstrong also gets another crack after 29 possessions for Perth last week.

"I don’t think it's this game that will determine anything for those guys. Seabs has been outstanding in his form for West Perth and he gets another chance. He is part of our future, having signed a two-year deal earlier in the year," he said.

"In Seabs' defence, we have a ruckman (Dean Cox) who can play 110 minutes and is dominating the competition, so it limits the time Mark Seaby can have in the ruck. When he has had long periods in the ruck he has performed very well, so hopefully tomorrow we can share the workload between the two and keep them both on the ground.

"Steven Armstrong continues to fight very hard with the way he plays. He has been up against (David) Wirrpanda, (Mark) LeCras and (Ben) McKinley, but gets another opportunity and the ball's in his court. I imagine he will share some workload in the midfield as well as up forward."

Joining Tim Houlihan, Darren Glass and Ryan Davis out of the side is Josh Kennedy, who is still battling an on-going knee injury. He could again miss several weeks with it.

"It's the same knee injury. He has the amount of rest required, works his way back through the WAFL, plays with us and it's still sore," he said.

"He's a kid that has enormous potential, but it's not the right thing to do to keep playing him when he's not 100 per cent fit. We are giving him the chance to rest again and he will play again if the build up of fluid in his knee goes away."