I remember him playing for Oxford. Never thought of him as a hard man but appears he was pretty tough.
Mick Harford was another who was hard as nails.
A lot of modern 'enforcers' like Robbie Savage and the like wouldn't have lasted 2 minutes in the 70's and 80's.
Apparently, Whitehurst was a bare-knuckle fighter in his spare time. There's a story somewhere of an incident during his time at Sheffield Utd; after the match, he was confronted by a gang of Sheff' Wednesday fans, so he picks the biggest one in the bunch and knocks him right out. KO'd. Seems he was a bit of an arsehole, but as tough as nails.
As for George Curtis, well, he was our Iron Man...didn't he own the Pub at HR as well, at some point? At 15 I was in there and got served by him, not knowing who he was at the time. Until of course, I was educated in detail by several of the older crowd.