Competition Problem 154a
composed by Vincent Labbé
South to make six spades against any defence.
Successful solvers: Steve Bloom, Ian Budden, Ed Lawhon, Steve McVea, Radu Mihai, Rajeswar Tewari, Wim van der Zijden. Sorry to disappoint those who missed line D below. Even though it has an alternative solution (now added), it strikes me as no less trivial than line C, which nobody omitted.
West’s best lead is a heart. North must ruff low and lead the ♠10, which East does best to cover. South wins with the ♠A (not the ♠Q) and leads the ♣Q, covered by the ♣K and ♣A. North cashes the ♠9 and South ruffs a club. Now the ♠Q from South exerts a seesaw squeeze on West in this position:
A. If West discards a heart, the ♠Q wins and South plays three rounds of hearts on which North discards the three diamonds. West is endplayed and must set up either South’s ♦K or North’s ♣10—in each case West’s top card is ruffed in one hand and the other hand then has an entry on a ruff to score the established winner.
B. If West discards a club, North overtakes with the ♠K. South ruffs a club and cashes the ♥AQ, North discarding diamonds. North’s remaining trump and two good clubs take three of the last four tricks.
C. If West discards the ♦6, the trick can be won in either hand to lead a diamond to the ♦A. West’s next lead concedes a trick in either clubs or hearts, to add to the ♦K, ♥AQ and a ruff in each hand.
D. If West discards the ♦A, South cashes the ♦K and, optionally, one top heart, before leading the ♥3. As in line A, North refrains from ruffing and so leaves West endplayed, this time in hearts and clubs. (Alternatively, North can overtake with the ♠K, and then South ruffs a club, cashes the ♦K, ruffs the ♥3 in North, who throws West in with a club for South to get three heart tricks.)
If West starts with the ♣K instead of a heart, that merely swaps the first and third tricks in the above line, giving the same ending.
See the solution to Competition Problem #4 for the recommended tabular format if you prefer not to write in English prose.
Hugh Darwen, 2018