Item Handoff (5e Variant Rule)
From D&D Wiki
When multiple characters are fighting over a single object, there is often a series of drops and handoffs. This variant rule is intended for individual scenarios, not to span an entire game.
If a creature is attacked (DC 8+damage taken), makes an attack (DC 8+damage dealt), or uses an ability that would be considered strenuous (DC 15), they must succeed a Strength or Dexterity saving throw or the item in question is dropped.
When dropped, the DM rolls 1d8. This roll determines what direction the item rolls with 1 being directly “above” the creature from the DM’s perspective and each consecutive number being 45 degrees (1 space including diagonals) clockwise from the last. The object rolls or flies 1d12x5 feet from the creature that drops it.