35-year-old Cox only lasted 75 minutes in Crewe's 4-0 defeat against Bradford City in the first round of the FA Cup.
Cox who was making a comeback from another injury which he sustained against Man Utd and was replaced by Darren Kempson who with his first touch managed to score an own goal.
The injury to Cox add's to manger Dario Gradi's woes and it seems that the inury list is not going down at all.
Gradi still has a host of players injured Baudet(Hamstring), Jones(Hamstring), Moss(Hernia), Maynard(Hamstring), Varney(Dead leg), Vaughan(Hamstring), O'Connor(Knee), Bell(Foot) and Matthews(Knee)