PORT Adelaide's untried young rucks are ready to step up in the absence of All Australian big man Paddy Ryder, forward Steven Motlop says. 

The Power could be without Ryder for the next six weeks after he re-aggravated an Achilles injury in his side's 50-point win against Fremantle at Adelaide Oval last Saturday. 

It's a huge blow for the Power and causes a selection headache for Sunday's encounter with Sydney at the SCG. 

Veteran swingman Justin Westhoff could be used in a stop-gap role along with Dougal Howard and Charlie Dixon, or the Power could bring in one of the three other specialist ruckmen on their list. 

Billy Frampton, 21, rookie-listed Peter Ladhams, 20, and Sam Hayes, the 18-year-old who was the No.47 overall pick in last year's draft, are the options at coach Ken Hinkley's disposal. 

"Paddy's a great player, he won our best and fairest last year and he's All Australian, but injuries happen in footy and our younger guys are hopefully ready to come in and take his place," Motlop told AFL.com.au. 

"It opens up opportunities for guys like Peter Ladhams and big Billy Frampton as well, while Sammy Hayes has been rucking really well in the SANFL in his first year.

"'Hoff' does a bit of the ruck, but it's up to the coaches who they think is playing well and who they want in the side."

Motlop had a day to remember in his first game for the Power, the former Geelong speedster showing his blistering pace against Freo on his way to 19 disposals and a couple of brilliant goals.

"I really enjoyed getting on the board early and it was a fun day," he said. 

"It's a very tight group, even only being here for five or six months, everyone's gelled together and the boys make you feel really welcome. 

"It showed on the weekend, everyone was just enjoying their footy."

Motlop played predominately in attack, but wants to move up onto the wing and through the midfield as the season goes on.

The Power have turned their focus to the Swans knowing these are the sort of games they need to win to be considered a genuine premiership contender.

"You want to prove yourself against the best sides and that's the challenge for us this year, is to do it against the best sides," Motlop said.

"They've got some great players and a great midfield and it's going to be a test for us.

"We're working on our defence and they've got big Buddy (Lance Franklin) down there that we're going to have to stop. 

"It's exciting for us and we'll prepare this week to take them on."