Plate

Striker inside; enemy raises left hand to head and lowers for inside hit; striker lowers point between enemy's arms, hand in Fourth, wounds before recovery
Striker inside; enemy raises left hand to head and lowers for inside hit; striker lowers point between enemy's arms, hand in Fourth, wounds before recovery De lo Schermo, overo Scienza d'Arme · Copenhagen, 1606 · Plate 65

Translation

This too is a Fourth, which wounds against a Third that wished to wound under the sword. The striker, being on the inside, feigns as though he would wound toward the right side of the enemy face; and the enemy wishes to parry with the left hand, lowering the body in order to wound below on the inside. But the striker, who had made the feint, taking the time of the raising of the hand made by that enemy to defend the head, lowers the point into the middle between one arm and the other in the very moment the opening is made, and, turning the hand into Fourth and turning the body with the left foot, wounds; and the enemy cannot parry, because the sword, shut between the two arms, remains in such a way that it cannot be pushed aside unless he changes his whole action.

The point of the play is very exact: the feint is not answered immediately by the wound, but by waiting for the hand to rise. It is the enemy's own defensive action that creates the new opening, and the sword is driven into the space between the arms before that improvised hand-parry can be completed.

Analysis

Initial guards You are inside; enemy intends left-hand parry plus low inside hit.
Wound Thrust in Fourth.
  1. You feint toward the right side of the enemy's face.
  2. He tries to parry with the left hand.
  3. He lowers the body to hit under the sword on the inside.
  4. You seize the tempo of his hand rising to protect the head.
  5. You lower your point between his two arms.
  6. In the same time you turn the hand into quarta.
  7. You turn the body with the left foot and hit.
  8. He cannot parry because your sword is shut between his two arms and cannot be pushed aside without changing action.

Translation note

The decisive action is: you exploit the opening created by the left hand lifting.
The Steel Marginalia · HEMA Study Group Notes in the margins. Truth in the bind.