Once 10 cards are dealt to both players, the player apart from the dealer has to start the game by drawing a card from the face-up card deck or from the face-down card deck.
When one card is picked, the player needs to discard another card. If the player is not able to use the card drawn, he/she can discard that same card, and it will be available for the next player to pick, who will then discard one of his/her own cards.
Both players follow the same gameplay in all their turns. However, a card drawn from the discard pile cannot be discarded again in the same turn by a player.
Gin Rummy consists of 2 players only, as compared to other types of Rummy being played with 2 to 6 players on a table in the rummy universe.
The cards dealt to each player need to be melded into combinations of 3 or more cards;
Sets (Cards with the same rank but different suits)
Sequences (Cards with the same suit but consecutive ranks).
In Gin Rummy, the Ace can only be paired with pip cards 2, and 3..., and not with the King(K).
Melding all 10 cards into sets and sequences in Gin Rummy is referred to as a “Gin”. When a valid Gin is declared, the player becomes the winner of that particular game.
When all the 10 cards of a player are not melded, the player can declare a “Knock”. In the case of a Knock, both, the knocking player and the opponent have an equal chance of winning the game. The sum of the actual card values of all the cards is compared between the two players. The player with the minimum total points (Addition of card values) is declared as the winner of that game (Any of the two players can be the winner depending on their card value).
Player 1 Cards: 1♥ 1♠ 3♦ 6♥ 7♥ K♦ 3♠ 4♦ 2♠ 2♣
Player 2 Cards: J♣ J♥ K♠ Q♠ 1♦ 3♣ 3♥ 7♦ 9♣ 10♣
Here, the total value of cards of player 1 is;
1+1+3+6+7+10+3+4+2+2 = 39
Whereas the total value of cards of player 2 is;
10+10+10+10+1+3+3+7+9+10 = 73
Since the Total Value of cards of player 1 is lower. He/she is the Winner of this particular round.
As per the Point system, if this Knock was declared by Player 1, he/she receives points equal to the difference between their card values i.e. 73-39 = 34 Points.
If this knock was declared by Player 2, then Player 1 receives points equal to the difference between their card values plus 10 extra points i.e. 73-34+10 = 44 Points.
When a Knock or a Gin is declared, the other player gets the opportunity to meld their cards and reduce their total card value. All the players during this time try to get rid of unmatched cards.
There is one more way in which a game can end, i.e. when there are only 2 cards remaining in the face-down deck. Such a game is declared null where both players get 0 points and a new deal is made.
Gin Rummy continues till one of the players gets 100 or more points. Points for declaring a valid Gin is 20, whereas in the case of a Knock:
Gin Rummy is a point-based game and hence, requires players to have the maximum number of points as opposed to their opponents. To accumulate these points, the players have 2 ways to win a partial game.
If a player can successfully meld all ten of their dealt cards into sets and sequences, they can declare a "Gin". A valid Gin automatically makes the player the winner of the partial game. Therefore, players should aim to meld all their cards to win in this manner.
The second way to end a partial game is to declare a "Knock". To do so, a player must have most of their cards melded, with a few remaining cards left unmelded such that the deadwood score is equal to or less than 10.
If a player declares a Knock, the other player has an opportunity to win by melding their cards with the opponent's and discarding them. The points for both players are then calculated as the sum of their deadwood cards, and the player with the lower score wins. The winning player earns points equal to the difference between the scores of both players. However, the player who declares a Knock has a lower chance of winning as there are several ways for the opponent to reduce their total deadwood card value.
Each card is valued according to its pip value i.e. The Ace holds 1 point, 2 holds 2 points, 3 holds 3 points, and so on. Face cards i.e. Jack, Queen, King are valued at 10 points.
When a Knock is made, and the knocking player has cards valued lesser than the opponent, then the knocking player receives a score equal to the difference in the total value of cards of the players. In case the total of points of the opponent is lesser, then the opponent wins the partial game.
When a player wins a partial game by going Gin, a bonus of 25 points plus the entire count of deadwood in the opponent's hand is added to the score of the player.
When the player not knocking has a sum of card values lower than that of the opponent, then it is called the Undercut. In such a case, the player not knocking receives an Undercut bonus of 25 points plus the difference in the sum of the value of cards.
Once the player gets to 100 points, the game ends and that player is declared as the winner. A predicated bonus is awarded to the winning player.
In a case where all of the cards in a player’s hand are part of a meld, that player can retain the last card and include it in a meld to be declared as a Big Gin. Here, 31 points are awarded to the player that declares a valid Big Gin.