One of the most valuable things a boxer can have is a tough chin. If you can take the biggest punch your opponent has to offer and just shake it off, that’s gold. It means you can walk in and have at it with immunity.
When that happens to a fighter during the war in the ring, when he takes what he knows is the other fighter’s best shot and survives it with ease, that’s when a fighter can really become aggressive and go after his opponent relentlessly — because there is little to fear.
So, paradoxically, a very defensive ability turns into pure offense.