i dont really feel hatton has much of a problem with southpaws.i thought he looked very impressive against thaxton ,smith, magee,hutchinson,and then he handled in close rugged fashion luis collazo.and lets be real collazo is at least the second toughest fighter that hatton has faced.if you include the wt factor along with his impressive skills, collazo could have defeated any of hattons previous apponents,except for maybe tszyu.could collazo have defeated magee? yes.phillips? yes.tackie? yes.maussa? yes.stewart, oliviera,?yes.tszyu? maybe. hatton struggled against collazo because he is a handfull period.and still overcame ,now lets compare the welterwt collazo vs castillos best apponents .collazo vs s.johnson ,?yes too big and strong.bazan?yes.lascano?maybe,good chance.casamayor?yes maybe,collazo is kind of a much larger version of casamayor.julio diaz ?yes easy.corrales?yes good chance ,that would be a great fight.now amagine castillo coming up to 147 to fight collazo.that would be a pickem fight,and if castillo won it would be a very close war.now looking at the collazo fight with hatton in that perspective i would say hattons win although not pretty was very impressive.now picture hatton vs castillo ,what a close match that should be.