As you know by now, at the deal, a hand may be considered a winning or losing one. If it is a winning type of hand, you should play it in an offensive manner, but if it is a losing hand it should be played with consideration to the defensive value of each discard until the hand changes. The expert player is one who can recognize immediately the changing value of his hand, and can adjust his strategy accordingly.
One of the most important strategic plays in gin is establishing certain cards for your opponent to throw, and holding combinations that can utilize the card that your opponent has been “encouraged” to throw. For example, you have a choice of breaking a 3, 4, combination or a 7, 8 combination and you know only that your opponent is holding a 7, 8, and 9 of a different suit. A good defensive layer would be more likely to throw the 9 that you need, since it would be thrown from a duplicated card in his own hand rather than a 2 or a 5 which he does not have matched up.
Another strategy in which expert players readily take advantage of is the unique situation called “on the turn”. Here is an example: Halfway through the deck you are holding a single King because you have believed from the play up to this point that your opponent is probably holding a pair of Kings, which he is trying to meld. At this point your opponent has decided to break his pair and discards his first King which you do not need. You are aware that because of the type of player he is, he would not at this stage throw one loose King from his hand. Therefore, you know he is breaking a pair, and you that so long as you have not picked this King, his next play will automatically be the other King.
Passing up his discard, you go to the deck and fortunately pick up the fourth King. Such a buy is called “picking on the turn”. You will hold this second king in your hand for one pick, and assuming that your conclusion was correct, your opponent’s next discard will be his second King which automatically makes a meld for you. The single exception to your holding a card for one turn is when your opponent picks from the stock a completely dead card and automatically discards it without putting it into his own hand.
The score at any given time should always be used as a forcing situation. A prime example of this is where your opponent is on a schneid or in danger of losing the game if he exceeds a specific count. If, for instance, his safe count is 8, you can afford to retain picture combinations knowing that if he were to pick a picture card he has no choice but throw it because of his count. This is a forcing situation that every expert player will take full advantage of. With a little luck and some expert play it is very easy to change the status of hand from a losing one to a winning one using these force methods.