Sancho was just doing what roosters do, and that alone doesn't make him "bad" by any means. Roosters by instinct want to be the lone leader and breeder of the flock, that's what they're born to do. But I know how sad it can be to see a dethroned roo. Maybe they will be able to live in peace together, we can hope. If possible, I think the best option is to seperate them and split the hens between them. If that's not possible, and the fighting doesn't stop, you may have to re-home one of them to someone who needs a good roo for their flock. Good luck and please come back and let us know what happens.