Yenda Blueheelers ? the top dogs of the Group 20 competition ? will be hell-bent on revenge when they face premiers Griffith Waratah-Tigers in a grand final rematch on Sunday.

The winner of the clash ?which is shaping to be one of the best of the season ? will earn a grand final berth and a crucial psychological edge over its competition rivals.

The loser will play the winner of Sunday's Yanco-Wamoon versus Leeton cross-town derby.

Despite an unbeaten season that will see them start commanding favourites to win the title, Blueheelers' coach Andrew Lavaka said there was "no risk" his side would go into the match overconfident.

"We might have finished on top, but they're the premiers," Lavaka said.

"You'll always be cautious of them and I really think this will be our toughest game of the year."

Worryingly for Yenda, an injury cloud hangs over star half David Rauluni (knee), second rower Trent McFadzean (hamstring) and bench player Daniel Judd (wrist).

Waratah-Tigers coach Mark Palmer was unmoved by any injury speculation, saying he was expecting to be confronted by a full-strength Yenda side on Sunday.

"There's always an element of cat and mouse at this time of year and we expect them to have a full complement," Palmer said.

"We're expecting a tough game and we'll have to improve on last week.

"We'll have to put pressure on in defence, move off the line quickly and dominate in the tackle.

"It's all to do with pressure. We can't let them get quick play the balls ... we need to nullify their playmakers."

He said while Yenda had danger men "across the park", the Tahs would be keeping a close eye on Lavaka, Rauluni and the Richards brothers.