I remember someone once said that Toney, although an ******* out of it, was never a particularly dirty fighter in the ring.
Now that you mention it, I've never though of him as a particularly dirty fighter while competing either. (His steroid use is another matter. Maybe 'roid rage is responsible for his sour temperament when he's not boxing.)
The opposite to this would be Carlos Monzon, a clean fighter in the ring and a good sportsman. Outside the ring he was one of the worst human beings imaginable
I got into boxing in the 80's and saw a replay of Monzon's last fight with Valdez. He was so in control in the ring I was surprised when I later learned of how bad he was outside of it.
Sandy Saddler,looked up interviews of him and he seems like a nice guy,but when you put those gloves on he'll absolutely destroy you.
The #1 niceguy act ruthless competitor, nasty fighter none other than Mr. Gene Fullmer. God help you if you fought him out west. I dont know if this counts as a dirty fighter when Ray Robinson negotiated in the contract to have the ring a certain size. He thought it looked small and ask for a tape measure. They gave him one and it measured perfect size. Ray accepted it. Turns they had cut parts of the tape measure out and glued it together. The ring was the size of a phone booth.