Trick-one blunders involving tenaces and entries

Larry Hammick
larry@hammick.com
2001.07.24

For some unexplained psychological reason, declarers make more
blunders on trick one than on any other. Many of these gaffes, perhaps
most, have to do with entries or tenaces or both.

One kind of error is to let the lead run up to a tenace, thereby
endangering a vital entry.
      Kx
      QJxx
      Kxxxx
      AK

      AJx
      xx
      Ax
      JT9xxx
On a spade lead 3NT is a laydown: Declarer takes the dummy's K, cashes
CAK, and has an entry in DA to establish clubs and another in SA to
cash them. But if declarer plays low from dummy on the opening lead,
he endangers three club tricks to gain one spade trick. If declarer
had only SAxx instead of AJx he presumably would not make this
mistake.

Another way to endanger a vital entry is to take an unnecessary "free
finesse".
      KJx
      Axx
West leads the 10 against NT. It is tempting to try the J. But if
declarer will need a later entry to hand _and_ needs to keep East out,
he must play low from dummy and (unless East puts on the Q) low from
hand as well.

Divided tenaces are also a trap: letting the lead run up to an
unsupported high card may risk an embarrassing shift by the defence. A
comical example from Reese & Bird:
           KT5
           AJ6
           83
           KJT92
     83            J9762
     T8742         K5
     AQ97          542
     74            A86
           AQ4
           Q93
           KJT6
           Q53
Against 3NT West led H4. With a little thought at trick one the
contract is cold: Win with dummy's ace and establish clubs. There are
then eight tricks and time to develop a ninth in hearts. But declarer
played low from dummy, allowing East to win and shift to a diamond.
The 10 and Q were played and back came D9, and the contract was
doomed.

In this next case there is no danger of a shift, but a trap is
nonetheless present:
      KQx         KQx
      A74         A74
      Qxx         Qxx
      J9xx        J9xx

      Ax          Ax
      QJ6         QT6
      AKx         AKx
      QTxxx       QTxxx
At left, West leads H5 against 3NT, Dummy plays low, and East puts on
the 9. You have eight tricks, and the ninth can only come from clubs.
As the defence has two stoppers there, you should _hold up_ your
double stopper in H. This play would be easier if you had Kxx instead
of QJx in H. At right, likewise, if East puts up the J at trick 1, you
must duck. In both cases, if you win trick 1, you will probably be
down whenever West has HKTxxx and one club entry.

When an honour materializes under one of his tenaces, a declarer may
be prone to cover it impulsively.
      KJx
      x
East has overcalled or preempted in this side suit, and West leads the
Q. If a shift by East would be unwelcome, declarer should not cover
with the K. He should play low. Now East can overtake and shift, but
only at the cost of a trick (assuming that declarer will have time to
benefit from the discards).
      Tx
      AJx
Against 3NT West leads low and the Q or K appears on declarer's right.
If declarer can place West with the length and can develop enough
tricks without letting West in, then he should hold up.

Last, declarer sometimes fears a shift by the opening leader. Second-
hand-high may then be necessary.
      T6
      AQ3
East has bid this suit and West leads the 8. To hold up the double
stopper without letting West shift, declarer should play dummy's ten.