I was reading an account of Foreman-Young and it said Foreman pushed, laced , and tried to break his left arm on the clinch. I have seen boxers forearm their opponents. Hard to say if it was intentional. It is in the boxers bag or tricks.
There’s also “heeling”, using the heel of the glove - which could involve possible lacing. As to the fight in question - while GF might’ve been guilty of some infractions, Young was a bit of moaner and whiner in general. And, IIRC, during the fight, Young was guilty himself of some of things he claimed George was doing. However, it seems as at the time, Foreman was the framed villain so Young’s own impure tactics weren’t necessarily highlighted.