Warriors fullback Kevin Locke faces up to a month on the sidelines with a damaged sternum after lasting just six minutes in his comeback from another injury.
The 23-year-old was forced from the field clutching his chest after a heavy tackle in the Anzac Day 32-14 loss to the Storm in Melbourne.
It was his first game back for the misfiring Warriors after he missed three NRL matches, and the trans-Tasman Test, with a leg injury.
The Warriors, who have lost three of their past four games and lie 11th on the table, could also be without prop Sam Rapira, who hurt an ankle against the Storm and it needs further assessment to determine the extent of the damage.
Playmaker Shaun Johnson is expected to be fit to face the Broncos on May 5 after sitting out the Storm defeat with a shoulder injury picked up on his debut for the Kiwis in the Anzac Test last Friday.
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