Crichton will fill the void left by Latrell Mitchell's exit from the club at the end of last season against the Super League champions on Sunday morning (6.30 AEDT) despite having never played the position in the NRL.

With young centre Billy Smith still recovering from ACL surgery, Robinson said it was the perfect opportunity to see how the talented former South Sydney man fares in a different role.

"It's something I have considered for a long time now," Robinson said.

"I talked to the coaches about Angus filling that role even before Billy got injured.

"But I am not locking it in long-term just yet. He is a high quality back-rower so I don't want to say he is going to play there for the rest of the year.

"It's a case of let's see how he goes and whether he takes to it."

The match at the exotically named Totally Wicked Stadium will see the premiers face a talented St Helens side that boasts Canterbury-bound Luke Thompson, widely touted as the world's best prop, and an attack that scored over 150 tries on their way to Super League success last year.

But new coach Kristian Woolf, who replaced Gold Coast mentor Justin Holbrook, acknowledges his side face a far tougher examination from the NRL Premiers.

"It's a great challenge and opportunity for us," Woolf said.

"I wasn't here last year but Saints certainly deserved their place here on the big occasion and I have been really impressed since I got here with the group I have got.

"They are hard working and honest as well as talented and I give us every chance on Saturday because of that."

Veteran Saints hooker James Roby said although his team are three weeks in to their season he expects the Roosters to still pose a formidable threat just as South Sydney did when they strolled to a 38-0 win in 2016.

"The Rabbitohs were very good that day and it was a lesson that we have to take these games very seriously," Roby said.

"I am sure the Roosters lads will come over, and despite not starting their season yet they are coming here desperate to beat us."

Australian Associated Press