Competition Problem 157b
South to make two spades against any defence.
Successful solvers: Steve Bloom, Ian Budden, Noer Imanzal, Ed Lawhon, Radu Mihai, Sebastian Nowacki, A.V. Ramana Rao, Zoran Sibinović, Rajeswar Tewari, Andries van der Vecht, Wim van der Zijden
Any club lead clearly concedes an overtrick. Against any other lead a club ruff by North would make the contract but two early trump leads would foil that plan. Suppose West leads a red suit and East cashes a winner in each before switching to the ♠5. West plays low, of course, but North wins with the ♠A anyway and advances a club for an avoidance play against Eastís holding.
A. If East plays low, South wins with the ♣A and leads the ♣5. If West rises with the ♣Q Eastís ♣10 will later be pinned so that South gets a trick in the suit instead of a ruff. Otherwise the club runs to Eastís ♣8 and the club ruff cannot be prevented.
B. If East rises with the ♣8 (or ♣10), South plays the ♣5. If West plays low, then North will get a club ruff, whereas if West overtakes South will again be able to pin Eastís holding and make two tricks in the suit.
The same play applies regardless of the number of red suit winners scored before the trump lead.
See the solution to Competition Problem #4 for the recommended tabular format if you prefer not to write in English prose.
Hugh Darwen, 2018