ST KILDA coach Alan Richardson has backed ruckman Billy Longer to bounce back against North Melbourne on Friday after a slow start to the season last week.

Longer was well beaten in the ruck battle with Stefan Martin in the Saints' win over Brisbane at Etihad Stadium, and has also been carrying a hip niggle.

The Saints named ruck back-up Rowan Marshall as an emergency last week, but the club is set to have an unchanged line-up in its Good Friday battle with the Roos this week.

Richardson said Longer was ready for the challenge of taking on Todd Goldstein, who had 35 hit-outs and 14 disposals in the Roos' loss to Gold Coast last week.

"Goldstein's playing good footy again, there's no doubt about that. He's been able to find some of his form that made him an All Australian ruck," he said.

"Billy probably lowered his colours last week to Stefan Martin, who's also in good form, but we need Billy to bounce back strongly and we need to be really competitive in that part of the ground."

The Saints are set to go in with the same line-up that beat the Lions comfortably last week at Etihad Stadium as they aim to open a season with consecutive wins for the first time since 2014.

"If we get through unscathed out here, and this is not much of a session, we'll go in unchanged," he said ahead of Thursday's light training run at the club's new headquarters, RSEA Park.

"We think that when the game was up for grabs and challenged strongly by Brisbane ... it was pleasing [we responded]. There was a lot to like about that and at this stage we'll go in unchanged."

They will stick with the same forward set-up, which included tall trio Josh Bruce, Tim Membrey and Paddy McCartin.

"I thought the guys did a pretty good job. Paddy had to play a pretty selfless role, it was a pretty high role, and 'Brucey' and Tim were able to get some pretty good look at it," he said.

"There's areas that didn't quite go as well as we'd like, but by and large, we were happy. Their function is to try and get a score for us and put defensive pressure on the opposition's rebound. Our outside game was pretty good, and they were a big part of that."

It will be the first time for the Saints on Good Friday, having replaced the Western Bulldogs as the Roos' opponent for the second year of the marquee clash, and Richardson said the occasion would be a good test for the club as it aims to maintain its unbeaten start.

"We'll just focus on the opposition and focus on what works for us. We got a lot out of last week's game. There were some things that worked really well for us, and some things like clearances that didn't go our way," he said.

"The Kangaroos are a really good clearance team, so we'll have to be at our best to give ourselves an opportunity to win. I think we'll handle it really well."