Bar a one-punch wonder from Holt (possible, but Hatton was usually pretty durable at his peak), Hatton would stop him get a rhythm going and stop him late.
Holt struggled with the tempo and pressure Bradley applied all he has to do was use his jab but he got lazy, Holt would have nightmares with Hatton because of the relentless mauling and body attacks. He may of dropped Hatton early in fight as he come in (over aggressive) but other then that Hatton would regroup and break Holt's heart around 10th or 11th.
Holt very early by devastating knockout. Holt can really bang and has ridiculous hand speed. Hatton to wide and wont be able to take many.
Hatton all the way, Holt is massively overrated for managing to headbutt Torres. Now Torres vs Hatton, that would be awesome! I think Hatton would possibly still take it, but not without problems, Torres-Cotto is a modern day classic
Hatton in his prime whilst not in the same class as Mayweather or PacMan would still beat the snot out of the Holts of the world. If Hatton were in his prime now he would have no problem with the Bradleys and Alexanders imo.