Well this example isn't exactly "Lacy'd" as this fighter got stopped. But Livingstone Bramble was highly rated P4P coming into his fight with Edwin Rosario, I believe Bramble was ranked as a high as 3 ? Or maybe top 5. And he got blown away by Rosario in 2 rounds. Bramble went from being a highly rated P4P fighter, to a journeyman fighter over night who ended up losing 20+ fights.
I'm not a brit. Few schoolings have been as bad as Calzaghe vs Lacy. Lacy was the closest thing to a punching bag. Everything Calzaghe threw was landing and Lacy was completely unable to do anything. It was comical. In most of the schoolings mentioned here, the winner still had some level of respect for the loser and the loser wasn't getting hit so ridiculously often. Trinidad vs Wright was embarrassing. But mostly because of the inability of Trinidad to get past that ****ing jab. Embarrassing to see such a highly rated fighter be that clueless. No other top guy Winky beat looked that stupid.
Not quite, but Briggs vs Vitali. Though Briggs was a complete punching bag that night, he wasn't highly rated I believe (or hyped at that late stage of his career). Still a horrific schooling.