Coach Tim Sheens has opted to shift Farah from his normal position at hooker due to the unavailbility of utility Tim Moltzen, who strained his hamstring against North Queensland last weekend.
Masada Iosefa will start at hooker.
“We are just working hard on those little things, keeping it simple with a new halves combination although Robbie and Benji have played plenty of football together in that configuration,” Sheens told the Tigers official website.
“Executing and defending, doing the hard things, kick and chase and defend hard, they are the little things you work on.”
The Rabbitohs claimed a golden point victory over the Tigers the last time to two teams met in round 5, but Sheens is confident his team will be stronger at ANZ Stadium on Sunday.
“Although they beat us with a last minute field goal in extra time, I think everybody knows on the day we led them by 12 points with 7 minutes to go, we should of won that game,” Sheens told the Tigers’ official website.
“We have got a lot of confidence from that. They had a full strength side in that day.
“I’m comfortable that our side is a better side. I know they are too, they are playing better football. They have got a couple of issues so we will be working hard to exploit them.”