The rule for third player to a trick 

Definition

You are defense and your partner leads a card, this puts you in the position of playing third to the trick, this is when you play your high card. There are exceptions  but on the whole it is a good piece of advice.

Examples of Third Hand Plays High

Partner leads the 4 and dummy has T 7 2, dummy plays low and you hold any of the following cards

• A 5           Play the ace
• K 9 6        Play the king
• A Q          Play the ace
• J 8 4 3      Play the jack
• 4 3            Play the 4 and partner will know you have nothing better

The Problem

There are exceptions to the "third position plays high" rule

Exception 1

If your partner on lead plays an honor for example a jack or queen, dummy plays low, and you have the ace , you should cover and win the trick

Partner leads the queen and dummy has 965 and plays low, win with the ace if you have one

Partner leads the jack and dummy plays low from T85, again win with the ace if you have one

Exception 2

If you have touching honors/cards, play 3rd hand "high," but with the cheapest in the sequence in your hand For example, partner leads the 2 and dummy has 9 8 4

• A K 7          Win the king, not the ace
• K Q T        Play the queen, not the king
• A Q           Play the ace
• Q J T 9      Play the nine, the cheapest in the sequence

Exception 3

If dummy one of the top three honors and you have a higher honor and dummy plays lowl withhold your honor and try to finesse with an intermediate card if you can
For example:

• Partner leads the 4 and dummy has Q 8 7 and plays low. You should play the Jack holding K J 2 or A J 2
• Partner leads the 2 and dummy has K T 4. You should play the 8 from A J 8 3