Whenever the ball is on a space with no card or where the card is not ready, the ball is ‘loose’.
For example, the ball is loose at the start of the game or after a goal.
Whenever the ball is loose, it will be ‘recovered’ to any adjacent (including diagonally) ready card, moving to that card. If the ball can’t be recovered immediately when it becomes loose, it will be recovered the moment there is an adjacent ready card (e.g. because a card is played or made ready).
If the ball is loose when the attack resolution phase begins, the attack automatically fails and the defender gains possession.