That's true but early on he was breathing heavily. I know the reason: adrenaline! He calmed down later and was at his most effective.
Prediction: Unless the Clinton campaign gets to Wallace or Fox News threatens him with firing unless he goes all in against Trump, Hillary will cancel the third debate due to a biased Fox News.
If Wallace, who as far as journalism goes is the best of this years moderators plays it fair, Clinton cannot win the debate.