File:Bridge auction competitive.png

English: A competitive bridge auction. Here, East opens 1♦ to show a 3-card diamond suit, and South, with close to opening values, overcalls with 1♥. West bids 1♠ to show length in spades. North bids 2♣ to show strength in clubs. East raises partner's suit to 2♠ South casts one more bid of 3♣. West, with a 7-card suit, raises to 4♣, but per the Law of Total Tricks, does not wish to raise to slam without further information in case East has only a 3 or 4-card suit. However, East, with a reasonably strong hand, uses the Blackwood convention (4NT) to asks for aces. East responds with 5♦ to show one ace. South passes, and with West only holding two aces, they decide to forgo the grand slam and bid 6♣, a small slam. The points awarded for making this contract is 620 (20 × 6 + 500) if not vulnerable and 870 (20 × 6 + 750) if vulnerable.