He was walking around the lane an hour before KO on crutches and wearing a big ski boot thing, didn't look good.
There is a reason youngsters should be used sensibly and not thrown in at the deep end, it is because they are not fully matured, Gareth Bale is still a boy and has three more years of growing up to do before he even starts building the muscle to reach his peak, this means that when lumping great defenders like Muamba pile into you at full speed you are liable to get injured when you are only just 18.
It does not mean you are injury prone.