Greate skill. It is very deifficult to fence on hands with such opponents. So, instead you need to swing his attention between foots and hands, kick his shins, knee, groin (use short strigth kicks, like shoot down snow from a tree), then attack his hands, fingers, menace to attack face, then kick his foot again, repeat with hands, etc. It will let to impose your own rhythm (see The book of 5 rings).