Fighters who have beaten the most defensive/elusive boxers

Hearns beat
Weston
Espada
Shields
Benitez
Duran

 

You can argue Floyd lost to Castillo and drawed with Maidana, but he clearly beat Oscar.

 

Chang could run through elite boxers at his peak. Zapata nor Sot could really do much to him.

 

Mayweather beat Marquez, Genaro, Judah, Corley, Canelo, Pac, Mitchell, and Augustus.

 

Tyson beat Tillis, Green, Biggs, Williams, Tucker, Spinks, Holmes, Mathis Jr., Tubbs, and basically Norris.

 

In the HW I would pick Rocky Marciano.
He beat some of the most technical boxers in the history of boxing:

• Archie Moore
• Ezzard Charles (twice)
• Jersey Joe Walcott (twice)

He also beat some great defensive boxers that are underrated nowadays but they were really so good:

• Roland La Starza (twice)
• Harry Matthews
  
• Don Cockell

He managed to beat one of the two greatest HW boxers of all time:

• Joe Louis (although he was old, he was still good, technical, strong and with still great footwork)

Combining his record he went 10-0 against one of the best defensive boxers of all time (Louis was more like an offensive boxer but he had good defense as well).

 

Kostya Tyszu beat, Mayweather, Hurtado, Gonzalez, Chavez, Mitchell, Judah, Leija.

 

Ray Leonard beat Wilfred Benitez and Roberto Duran (x2), two of the greatest defensive fighters of all time.

To that you can add:

Andy Price

Floyd Mayweather Sr

Adolfo Viruet

Randy Shields

That’s seven wins over gifted defensive fighters, including two all-timers, in a 40-fight career. Not bad.