Leeds forward Weller Hauraki has been ruled out for up to three weeks with a calf strain.
Hauraki, 27, picked up the injury in Sunday's 44-16 win over Widnes, although the positive news for him and the Rhinos is that he hasn't suffered a tear.
The Kiwi, who signed from Crusaders at the end of the 2010 season, has already begun rehabilitation with the Rhinos medical team.
He missed just three Super League games for the Rhinos last season, and was an ever present for Crusaders in 2010, scoring 11 tries.
Castleford centre Michael Shenton says his recovery from a knee reconstruction is going well and he is hopeful of being back on the park for the Tigers this season.
Referees Richard Silverwood and Sam Ansell have been ssuspended pending the outcome of an internal investigation.
Bradford have signed former London halfback Joe Keyes on a three-year deal.