The 2018 IBPA Awards included, for the first time, a ‘Computer’ Award,   The awards was jointly given to Bridge Baron for its fine defense on the deal below from the 2017 World Computer-Bridge Championship, and to journalist Ron Tacchi for his writeup in the IBPA publication.  The deal first appeared in my writeup in the 2017 day-by-day  and also on the WBF website.

A cat and mouse game between Bridge Baron and Micro Bridge ended with Bridge Baron succeeding by unblocking the ♦KJ.

Board 20
Dlr: W
Vul: Both
.
.		 North
♠ K642
♥ 86
♦ 86
♣ Q8632
West
♠ AT7
♥ 42
♦ KJ732
♣ K75		 East
♠ QJ953
♥ T9
♦ QT4
♣ JT4
South
♠ 8
♥ AKQJ753
♦ A95
♣ A9
West
Bridge Baron
1♦
All Pass		 North
Micro Bridge
Pass
.		 East
Bridge Baron
1♠
.		 South
Micro Bridge
4♥
.

A trump lead defeats the contract, depriving declarer of a diamond ruff. Bridge Baron led the ♥4, won by declarer. After cashing a second trump, South led the ♠8, correctly won by West’s ace. West continued with a low diamond (the jack or king is best catering to partner holding queen third, continuing with the other honor when declarer ducks), to partner’s queen, and ducked correctly by declarer. Now East did not find the club return to take the pressure off West. The diamond return was won by South and on the run of trumps, West avoided the endplay by discarding the ♦KJ, allowing partner to win the eventual diamond return with the ten! Down one.

This deal demonstrates the difference between human play and the current state of the art in bridge bot play.  Human experts have a relatively easy time visualizing the play early in the play, while current bot simulation techniques make it somewhat difficult to defend early in the play and quite easy in the end game.  Here West might see the need to avoid a club endplay, and lead a high diamond at trick four, even though there are many layouts where a small diamond is best.  Bridge Baron lead of a small diamond might be the choice of humans as well.  To Micro Bridge’s credit, it declared perfectly, setting up the endplay, but Bridge Baron countered in the end game by discarding the two high diamonds.