Give 3 examples of 3 matchups that include BOTH boxers in their prime!

DLH-Whitaker was a nightmare to score.

Whitaker's peak was late 80s/early 90s, at 135 and 140. I don't think he was as great at welterweight and up, but I'd still pick the Whitaker of 1993-95 to win competitive decisions over DLH & Trinidad at 147. Whitaker started really declining in 1996, with the Rivera fights and his struggle with Hurtado.

I think Whitaker trained harder for DLH though so he was in better form than he had been for his last few fights. Perhaps he stopped doing coke or went easy on it in preparation. It was that last great performance by an aging fighter that Cus D'Amato talked about. Unfortunately the greatness was all on the defensive end. I had the fight even and have no issue with DLH winning. Although the judges having it 9-3 for Oscar is extreme. It was very close.

To get back on topic, Leonard-Hearns 1. Leonard-Benitez also, although you can argue that Leonard was a tad inexperienced. But he was very seasoned for a young contender, MUCH more seasoned than most fighters nowadays who were highly marketed, well-touted amateurs and challenge for a world title for the first time.

Mayweather-Castillo
Mayweather-Corrales

 

DLH vs Tito was slightly past his prime.

DLH prime (best form) was at 130-135 he was very powerful vs the shorter, less skilled fighters.

At 147 he faced a solid Tito, who started at 140, but was still in top form at 147

Quartey was also solid at 140, but was still in top form at 147, because he was very solid built 140

DLH was not in his prime (weight) 130-135, his skills & reflexes still extended up until early 2000s, but career wise he was coming of his prime as soon as he left 135.