How have you tried to encourage him to accept the lead? It is obviously not working just putting it on. How about using really tasty treats like chicken. Call him to you with the lead on the floor, give him a bit of chicken once he has done this. Then let him smell the lead, if he tries to run then you will need to tempt him again with the chicken. Don't ever put it on when he is unsure otherwise it becomes a negative experience. Also maybe try putting it on in the garden.