While Cronk is in major doubt for Sunday's contest against his former club due to a shoulder injury, Munster believes both parties have moved on since their split at the end of 2017.

"He's playing more elusive, a little more off the cuff sort of stuff," Munster told AAP.

"Everyone knows what Coops is like structure wise and he's really good at that.

"He's brought a bit of structure to the Roosters side and they've shown him a bit of ad lib footy as well and that's really dangerous."

Munster admitted he would have some nerves lining up against Cronk, who spent 14 seasons with Melbourne.

"Everyone knows that Cooper's a great player and he really thrives in the big moments," Munster said.

"I will be really nervous if we play against him because we know what he can do and provide in big games and we know we'll have to nullify him."

He said that given both Cronk and the Storm knew each other so well neither would have an advantage in the title decider and it would come down to who executed best.

"He knows the Storm backwards for sure but we know him pretty well," Munster added.

"We just need to focus on ourselves as we know what he's going to do but if we stick to our game plan and stick to what we're good at it will go a long way to us winning the grand final."

Despite the threat that the former Test and Queensland Origin halfback posed Munster said Melbourne still had plenty of affection for their former player.

"I will be out there to give him a bit of niggle and let him know I'm out there but it's just fun and games."

Australian Associated Press