Putting the brakes on Richmond’s attacking raids out of their back half is high on St Kilda’s list of priorities for Friday night’s AFL semi-final at Metricon Stadium.

The Saints will go into the do-or-die clash with a smaller forward line than usual after Paddy Ryder was ruled out with a hamstring injury.

It means Rowan Marshall will play almost exclusively in the ruck, with Jonathon Marsh coming in for just his second game in three months to bolster the stocks.

Josh Battle and Shane Savage replaced unavailable defenders Jake Carlisle (family reasons) and Ben Long (suspended).

Max King, Tim Membrey and Marsh are set to play key roles in the aerial contest with Tigers defenders David Astbury, Nick Vlastuin and Noah Balta.

“Their intercept marking, when they do that well, they’re hard to stop,” St Kilda coach Brett Ratten said.

“That just really builds their offensive game and we have to take that away from them.

“They can’t mark the footy in our forward line to start their counterattack and their (possession) chains that they do so well.

“That will be the challenge for us and there’s aspects of their game that we have to respect, but hopefully they’re thinking about what we can do and our potency as well.”

In Ryder’s absence, Marshall will be called on to step up and shoulder a bigger workload against dual premiership ruckman Toby Nankervis.

“He’s been ready to go, he’s been looking to play more ruck time and this is a great opportunity for him,” Ratten said.

“That’s why we brought Paddy in, to make sure that they were fresh at this time of the year.

“It’s been a big workload for some of the ruckmen in the competition that have had to do it by themselves.

“It’s right at the pointy end and there’s only a few games to go, and I think he (Marshall) will really thrive in this environment.”

Richmond made two changes at selection, bolstered by Tom Lynch’s return from a hamstring injury.

Nathan Broad was also recalled while Mabior Chol and Jake Aarts were omitted.