Jarome Luai's hopes of reviving Wests Tigers' stalling NRL season have been dealt a blow, with the five-eighth ruled out of his side's clash with St George Illawarra.

Luai will not take the field at Kogarah on Saturday after the playmaker experienced delayed concussion symptoms following Sunday's 12-6 loss to Newcastle.

After starting the season strongly, the Tigers have won just two of their eight games since Luai announced his intention to move to the PNG Chiefs in 2028.

The Tigers' form slump has coincided with a heavy injury toll, with centre Taylan May also ruled out of their trip to face the Dragons with a long-standing shoulder issue.

In Saturday's late kick-off, Brisbane have been forced into mass changes through injury and State of Origin selection as they host Cronulla.

Such is the extent of the Broncos' list of unavailable players, which includes winger Josiah Karapani following his drink-driving charge, only five remain from Michael Maguire's round one team.

Deine Mariner returns on the wing for Maguire's side after being out with acute compartment syndrome in his thigh, while the Broncos are seeking an exemption to allow Xavier Willison (concussion) to be cleared to face the Sharks.

Australian Associated Press