Seven of hearts turned up.

THE PLAY.

Trick 1.

Tricks AB, 0
YZ, 1
1. Z A↷ Y B
A♠ 8♠ 4♠ Qn♠

Trick 2.

Tricks AB, 0
YZ, 2
2. Z↷ A Y B
3♣ 7♣ Knv♣ 4♣

Trick 3.