The Sydney Roosters are increasingly confident they will have maverick centre Joey Manu on deck as they seek to beat Cronulla and keep an unlikely NRL finals charge on track.

Written off by pundits at the end of July, the Roosters have confounded expectations to make it to week one of the playoffs with a run of five straight wins.

Things seem to be clicking at the right time for Trent Robinson's men and they will travel to PointsBet Stadium for Saturday's elimination final buoyed by last week's victory over South Sydney.

They were without Jared Waerea-Hargreaves (suspension), Daniel Tupou (knee) and Manu (hamstring) for a gutsy win, which consigned their bitter rivals to a year without finals.

Manu's replacement - one-time Queensland State of Origin fullback Corey Allan - did exceptionally well to shut down Souths' electric left edge while filling in at right centre.

"To lose Joey, Jared and Toops (Tupou) last week wasn't ideal for us, but I thought Junior (Pauga), Corey and those middle forwards did a fantastic job," said five-eighth Luke Keary.

"If we get Joey back then that's great, but I've got a lot of belief in Corey because he's such a good footy player.

"They pushed Joey a little last week...we haven't trained yet this week so I'm gathering they'll give him every chance."

Tupou was seen at Roosters HQ on Monday in a knee brace and is rated no chance of featuring.

But reigning Golden Boot winner Manu is set to increase his workrate this week in a bid to ensure he is fit to fire against the Sharks.

"Hopefully Joey should be right come Saturday," said back-rower Nat Butcher.

"I know he's done all the weights and that stuff, and I think he's now starting to get through that running process and ticking some boxes before joining the team later in the week.

"Joey is a great player and one of the best that we have.

"He's a player who knows how to excel in the big moments in the big games and under the most amount of pressure so it'd be great to have him back if he can make it."