We play by the old-fashioned (original) canasta rules (not the American). Question is: if your opponents make a canasta, and you hold two cards in that rank, and the opponent to your right discards that rank, can you pick up the pile? Is this different with different sets of rules?
Yes, you can, (For example, your opponents have a Canasta of 9s, and you have two 9s in your hand, and then they discard a 9).
But I'm wondering why they would discard it instead of adding it to their Canasta (unless you have the rule where once you get a Canasta, you put that pile aside and it is not allowed to be added to).