Former Jet Jim Mckenzie was very tough and Stan Jonathon was one of the toughest ever.
In the toughest "pound for pound" fighters-Stan Jonathon was very hard to beat. At 5'-10, and weighing around 165lbs. he took on and beat some pretty big guys-"like Bouchard" ( never forget that fight)
Other tough smaller "pound for pound guys"
1) Stan Jonathon ( 5' 10" tall)-Boston Bruins
2) Tie Domi- ( about 5'9" tall)
3) Tiger Williams ( very tough-smaller side)
4) Bob Gasoff ( St.Louis) - 5'10" tall- Tiger Williams said he was the dirtiest toughest guy he's ever fought. Gasoff died young in a motorcycle accident. ( he would gouge guys in the eyes, and shove his finger in their ears-and twist apparently-"just an animal)
I'm no expert on these "pound for pound" best fighters, I'm sure there's a lot more- but it be hard to beat "Stan Jonathon"-one tough customer at 160lbs who'd fight anyone. His fight with heavyweight Bouchard is sure a "classic."