I think he goes 0-4 . With his power, in a sleeper capacity if his best and meanest shows up, he is dangerous though , no doubt.
Baer never stopped someone cold with 1 punch as far as I know. He had hurting punches, that is different.
Tua was too stone chinned for Baer to take him out, though I would say that maybe he was limited enough to where Baer could've outboxed him- If Baer knew how to box that was.