Interesting, never thought of that.

I'm no expert, but I'd guess that just about everybody gives off unconcious signals of one kind or another. It wouldn't surprise me that a guy like Ali, if he is very adept at recognizing patterns quickly, would be able to detect some kind of a signal or body language that would give him an idea what was coming. Especially if he hought the guy a few times, e.g. Frazier, Norton etc.

You'd have to be damn good at reading the signals, but sure I think it could happen.