The Warriors have confirmed medial ligament damage to his right knee will keep winger Manu Vatuvei out of NRL rugby league action for up to eight weeks.
The club's 25-year-old record try scorer was forced off the field just 14 minutes into Saturday night's NRL season-opening 'Battle of Eden' against Parramatta after his opposite Etuate Uaisele halted him with a torpedo-like tackle.
Uaisele's head collided with Vatuvei's right knee, bringing an unwanted end to the night for the Warriors' 2010 player of the year.
The initial prognosis on Saturday night pointed to Vatuvei being out of action for six to eight weeks with medial ligament damage and scans have confirmed the initial assessment.
Surgery isn't required.
Vatuvei's replacement will be known later today when Cleary names his team to face the Tigers in Sydney on Saturday night.
Meanwhile, the Warriors standoff James Maloney has been handed a grade one dangerous contact charge by the NRL's match review committee following a second half tackle on Parramatta fullback Jarryd Hayne on Saturday night.
Maloney is likely to miss one game after taking an early guilty plea.