An interesting deal arose in a recent junior training session. With neither side vulnerable, you hold:

Partner deals and passes, righty opens 1♣, and you double. Lefty passes, partner advances 1♠, which gets passed around to lefty, who doubles. Partner passes, and righty bids 1NT, ending the auction.

You play upside-down count and attitude but you aren't a regular partnership, so that's about the extent of your carding agreements.

What is your opening lead?

A spade looks clear. A spade lead might cost a trick in the suit, but if partner has an entry it's more likely to be in spades than another suit. It might be necessary to set up spades at once, even at the expense of a natural trick.

You lead the ♠3 and see:

Declarer plays the ♠10 from dummy and wins partner's ♠J with the ♠K. At trick two, declarer leads the ♦3. You give count with the ♦6. Dummy's ♦Q wins, while partner follows with the ♦4.

Next, declarer runs the ♣9, then plays ♣K and another club. Partner, who started with ♣Q53 plays ♣5-♣3-♣Q. As declarer plays the fourth round of clubs, this is the position:

What do you discard?

It probably doesn't matter whether you discard a heart or a diamond. You choose to discard the ♦5. Dummy discards the ♠5, and partner discards the ♥5.

This is the position:

Declarer leads the ♠4. Up or down?

You should rise with the ♠A. Only if declarer is being very tricky with ♠KQ4 could this be wrong, and partner's carding suggests that is not the layout. The ♥5 discard can only be an encouraging card if partner has exactly ♥K85. More likely, partner started with ♥543, ♥542, or ♥532. Additionally, partner might have chosen to play the clubs up-the-line with particularly weak spades. The echo in clubs sounds like a spade card. Failing to rise with the ♠A could get you endplayed.

You go up with the ♠A, as partner follows with the ♠2. What now?

Cash the ♦A! You will take partner's spades next, but first you need to unblock the ♦A in order to have a sure beat. On the fourth round of spades, declarer will be squeezed down to ♥Kxin order to keep the ♦K, so you will take the last three tricks in hearts.

A squeeze by the defense is already uncommon, but a defensive Vienna Coup? Even rarer.

The full deal and play: