The reigning All-Australian big man will be sidelined for up to a month after surgery last week to a compound fracture in a finger.
Cox, 31, dislocated a finger and split skin open in the incident during a training drill.
The champion big man is understood to have spent a night in hospital as a precaution against any infection which could have further delayed his recovery and planned return to full training.
His injury has been widely reported as just a dislocated finger with minor hiccup to his training and final stages of his pre-season campaign.
The six-times All-Australian and 2006 Eagles premiership ruck force seems in no doubt to miss the start of the AFL premiership season against bitter enemy Fremantle on March 23.
It is believed that a “best case” prognosis for the powerhouse on-ball enforcer is that Cox could make it back into playing in time for West Coast’s final NAB Cup clash against Port Adelaide in Alice Springs on Saturday March 9 ahead of the summer competition grand final a week later.
Cox looks certain to miss West Coast’s opening NAB action in the triangular “lightning carnival” concept against Fremantle and Geelong in Perth on Saturday February 16.
It is understood he is already expected to miss the NAB clash with power club Collingwood in Perth again on Sunday March 3.
Cox joins his powerhouse ruck partner Nic Naitanui on the playing sidelines suffering injury of different kinds.
Naitanui, 22, is undertaking a much longer rehabilitation as the reigning All-Australian lead ruckman recovers from groin surgery back in November.
The athletic potential match-winner is not expected to resume full training until late into next month and is certain to miss early important games of the 2013 premiership home-and-away season.
Projections for Naitanui’s return are believed to consider missing early games and potentially not even a comeback until as late as Round 8 in mid-May.
Cox, who has played 251 Eagles games since his debut back in 2001, has been in stunning pre-season training and skills form in preparation to lead the potent West Coast on-ball division in tandem with fellow veteran Daniel Kerr and young top guns Scott Selwood, Luke Shuey, Matt Priddis and Andrew Gaff.