The 25-year old fell awkwardly fifteen minutes into the Wanderers 2-1 defeat by arch rivals Manchester United on Wednesday night after he attempted to tackle the United youngster Darren Fletcher and was strechered off the field of play a moment or so later.
Emerson Thome replaced the wing back Gardner as Bolton moved Simon Charlton back to a more familiar role on the left hand side as Wanderers wait anxiously for news on the Jamaican's condition.
More will be revealed once the player has further tests to show the extent of the damage but it is a huge blow for the Trotters who had just gotten Gardner settled into a more defensive role.