A-B win 30 by honours.
Y-Z win 2 by cards.
Trick 1. Y plays King second hand, hoping it will be taken by the Ace, so that he may become third or fourth player, and perhaps save his Ten. B, with the minor tenace in trumps, plays to avoid the lead as long as possible.
Trick 2. Y gets rid of another winning card; B keeping a small card to avoid the lead.
Trick 3. A returns the Club, reading B for the Q or no more. B still avoids the lead, and Z is marked as not having the trump Ten, or he would have saved it.
Trick 4. Z plays to win what cards he can.
Trick 5. B throws ♢A to avoid the lead, knowing Y has the trump Ten; for A would have made it on the second round of Spades. A also marks it with Y, as B does not save it.
Trick 6. B is not sure whether Y has a Diamond or a Club left, and discards the winning card.
Trick 7. Z plays Queen to shut out the Ten, if with A. A knows each player has two trumps left, and that as the turn-up is still with Z, B must have J or K; for if he held only 7 and 6 he would have trumped in to make cards.
Trick 8. A leads trumps. If Y does not play the Ten, and B has not the Jack, B must make four cards and the King by passing. If B has the Jack, he must catch the Ten, no matter how Y and Z play.