Gin Rummy strategy

A king you are hoping to pair with is ten points of deadwood every turn you keep it. In the first few turns the cheapest hand is usually the best hand — you have not committed to anything yet, and ten points of leftovers is the whole knock threshold.

A 7 can run four ways — 5-6-7, 6-7-8, 7-8-9 — and an ace or a king can only run one. When two cards are worth keeping for the same reason, keep the one nearer the middle of the deck.

Every card your opponent takes from the pile narrows their hand to a few possibilities, and every card they throw rules something out. If they pick up the 6♣, stop feeding them 4♣, 5♣, 7♣ and 8♣ — and note that they are probably not collecting sixes elsewhere.

A knock at 8 deadwood on turn six usually beats a perfect hand on turn fifteen. The longer a hand runs, the more likely your opponent is the one who gets there first — and a 3-point win is a win. The exception is when they have taken nothing from the pile for several turns, because that is what a hand going gin looks like.

Your melds are what their deadwood escapes onto. Knocking with 9-10-J♥ on the table when they are visibly collecting hearts can turn a 6-point win into an undercut. Sometimes the right knock is the one where your melds are sets rather than runs, because a set has only one card that extends it.

When the stock is nearly gone, a hand that ends undecided scores nobody anything — so if you are ahead in the match, running the stock out is a legitimate way to protect a lead, and if you are behind it is the outcome to avoid. Three such hands in a row end the match on the score as it stands, so a lead you cannot extend is a lead you can sit on. Watch the count, not just your hand.