TRICK 1.--Z must save an entry card for the spade suit.
TRICK 2.--A refuses to part with the control of the
adversary’s suit.
TRICK 3.--Should Z not overtake the jack of spades, A would
again refuse to part with the control, and hence this entire suit
would be blocked. This situation frequently occurs and is often
misplayed. When your cards are in sequence and should you know that
the adversary is holding up, always overtake to obtain the lead so
that you can continue to establish your suit.
TRICK 4.--A cannot afford to lead any other suit and
continues with the diamonds.