Just as there is strategy when playing against an offensive player, there is also specific strategy that you can employ when you are playing against a defensive player.
Against a defensive style player, unless it is very early in the hand, you should not knock. Instead you should play for gin. When you do not knock a hand, your opponent is unable to lay off cards and the major purpose of a defensive player is to hold the cards he knows he will be able to lay off. The holding of these cards seriously hampers the offensive construction of your opponent’s hand. Frequently you will find that you have thrown him off balance to the extent that he now starts releasing these lay-off cards immediately. When this occurs, you should start knocking against him and you will have your opponent in a total state of confusion.
Another method that is good against a defensive player is the frequent picking of stiffs or speculative cards. This will force him to destroy the offensive value of his hand by holding as many of the surrounding cards as he can. Against a good defensive player, however, you should make it a rule not to throw back any stiff that you have picked once three more cards have been played. From the play of these cards, your opponent will quickly become aware of the fact that your pick was a stiff and he will attempt to buy sufficient cards to completely tie up this card. He will thereafter hold combinations that your stiff could be used with, knowing that so long as you hold the card it will be useless to you, so eventually it will have to come back to him.
For example, suppose you had picked the J♥ from your opponent and he has the 7♥, 8♥, and 9♥ in his hand plus the Q♥, and J♣. He subsequently picks the J♠. He now knows that the J♥ which you picked was a stiff and is completely useless in your hand. If given time, he will establish his own hand into seven-melded and retain his own two Jacks and the Q♥, thereby killing your hand. If you should release the J♥ in order to make another combination you will automatically gin him.
When picking a discard, do not throw back any discard that will indicate how you are using the card that you picked. In other words, if you were to pick your opponent’s 10♣ discard, try to avoid discarding another 10 since you do not want to show him that the card you picked was for a club run. Force him to hold back the 10’s as well as the clubs.
Keep in mind that when you are playing against a strictly defensive layer, he will, once you have picked a card from him, take every step necessary in his own hand to tie up in a meld whatever card he is forced to hold against. Therefore do not throw any card which would help him accomplish this task.