Look at 19 into this clip and you will see Chris appear to set down on his lead right leg to crank the crocodile kick with his rear leg. This is the up-jab chamber position for driving up into the chin, with left calf and right thigh extension. He then does a slow, sliding lunge, with no real upper body effort, and all leg. You kickers, with those sweeper back thighs, this is something that should be in your boxing game. It was what was behind the success of that jerk “Macho” Camacho, his leg strength, which pairs more productively with a jab than anything.
The up-jab can be delivered in pronated, vertical or supinated [ideal, as it lifts the chin better and enters the eye-socket with bare-knuckles] fist. In a bare knuckle situation, launch this from the outside over his lead hand or rear hand, with your forearm sliding over his, and up into the eye socket with the two large knuckles as you roll your fist back to a palm up supinated position.