South, with 13 HCP and five hearts, opens one heart.
North has a hand good enough to raise partner to two hearts even if he only had three hearts. But with five-card support and a fear of opponents having their own game, he raises to game.
The contract: Four hearts by South
The opening lead: The ten of spades
Declarer wins the ace of spades and draws three rounds of trump ending in dummy.
Declarer only needs two ruffs in each hand so drawing three rounds of trump is the best strategy. He plays a small diamond to the king and jack. East plays the ace as the dummy has a singleton and returns the king of spades.
Declarer ruffs and then loses three club tricks. Declarer loses four tricks in total to go down one.
One cannot be upset about going down one and giving the opponents 50 points.
If the opponents find four spades, they will get 650, a sizeable difference. Because North jumps to four hearts East cannot come in with spades or diamonds. They are cold for five of either suit.
The result: Four hearts down one for -50
Notes: -The requirements for a weak jump to game of partner’s major are five-card support and less than eight high card points. If vulnerable, one should also have a singleton.
-One cannot be too strong and miss slam.
-If vulnerable or with spades not hearts, one might just bid two spades with the intention of making the contract. When one bids game with a five-five fit, one is not bidding to make. One is often trying to prevent opponents finding their contract.