I am not so sure about this.
I have watched every fight from the last three years from Marquez many times over - Diaz, Katsidis, Diaz again, Casamayor, Mayweather - and I'm not sure how much he's really lost.
Marquez was always a fighter that relied on counterpunching and timing, not outright speed, so even if he did lose a little (which I don't know that he has) I don't know how badly it would affect him.
Whoa - let's get one thing straight - Pac wasn't drained for either fight. He's only 5'6", and he can't even hit the welterweight limit consistently. Those fights were fought by two prime fighters in the weight class they were most comfortable in.
However, that being said, he is bigger and stronger and he is more skilled. But as the saying goes, styles make fights. Marquez is the Ali to Pac's Frazier - he is quick, he hits hard, he thinks his way through fights, and makes adjustments.
Is it possible for him to get KO'd - sure is. I really don't know how this fight will turn out, but given Marquez's age and his propensity for getting knocked down, I'd say it's possible he'd lose.
But Marquez so thoroughly dominated the first fight (after the first round) and his performance in the second tell me that he has all the tools to do it all over again.
It's just how he is that night when he steps in the ring.
Nah. He hasn't fought like that in sometime. He's bigger and faster and more accurate and that fight is going to turn out a lot more one-sided than people think it is.