Douglas via competitive, but clear UD. Mercer's had a lot of success against Lewis because Lewis is heavy-footed & not too quick on his feet, so he was able to draw him into a dog-fight. Douglas wouldn't take the bait. He had the good lateral movement & quick feet to neutralise Mercer (along with his long jab that was better than Lewis's IMO). He wouldn't be drawn into a dog fight & would be rallying up points early, so that by the time he slows down, Mercer won't be able to capitalize on getting the win in the later rounds. Mercer's gas tank also wasn't great, as he would have slowed considerably from exhausting himself in the early rounds where Douglas is boxing.
Douglas was dialed in and wouldn't be brawl happy like Lewis seemed to be, so Mercer isn't hitting Douglas at will. Plus, when was the last time Mercer did anything well against 80's heavyweights?
