Tricks AB, 2
YZ, 0
2. A↷ Y B Z
A♦ 8♦ 7♦ 4♦
Trick 3.
Tricks AB, 3
YZ, 0
3. A↷ Y B Z
Kg♦ 9♦ 7♣ 10♦
Remark (Trick 3).—The knave of diamonds, and therefore the command of trumps, is marked in Y's hand.
Trick 4.
Tricks AB, 4
YZ, 0
4. A↷ Y B Z
Kg♠ 4♠ 3♠ 7♠