Puzzled by the foot

i help with my local rugby club doing physio, one of my players has had problem with this foot since september. he has been for Xray, no bone damage, no pain in any movements ie dorsi & plantar flexion but hurts if i have to touch the top around about the narvicualr bone. he can run for a short while but pain is present.
anyone ANY ideas, this has been driving me mad!! thamx rini-bo