Prime 4 prime I'll go Sugar ,but a evenish fight for at least 6 round. Then Leonard steps it up and goes to work .Can see Sugar nailing him with hooks until Curry crashes .
Ray stronger than Donald. Nip and tuck early, until 9th round, where Leonard explodes, hurting Curry. Ray by 12th round kayo.
Leonard would be to much for Curry. Curry would have his moments but Leonard's superior all around ability plus his much better chin would lead to Curry's demise within 7rds