Leonard was at his prime best at welterweight. Even he said that he would be a nuisance at middleweights. He struggled mightily at weights above 154 and although he was blessed with wins over a fading Hagler and a dehydrated Lalonde, he barely made it to the finish against Duran and Hearns at super middleweights. He was also routed by Terry Norris when he made an attempt to drop back at 154.

I think Leonard vs. Greb would be like Robinson-LaMotta 1.

Using the rules and ref of his time Greb wins this fight. He manhandled people and lots of things that were legal then are fouls now.

So back in the day he pummels Leonard into submission in less than 10 rounds.

Greb by unanimous decision. Leonard just wouldn't throw enough to keep Greb off him. Greb's volume punching would give him the win

At 147, Leonard edges out Greb because of his speed and boxing skills. At 160, where Ray would be slower, Greb would outpunch him.

Sugar Ray Leonard on points.

If Roberto Duran and Tommy Hearns can frustrate and beat up on Sugar, Harry Greb could do it no problem, From what I've researched on Greb, in his prime he would have beatin most in his prime

Greb KO