The poker games in A Streetcar Named Desire serve dramatic as well as symbolic functions. The first game brings Stanley's male friends into the apartment, allowing Blanche to meet Mitch. The second gives a reason for Mitch to be present even after he has broken off his relationship with Blanche. Stanley's focus on the poker game and his irritation that Mitch does not take it as seriously as he does provides a foil for Mitch's more sensitive nature.

The poker games are also symbolic. Poker is a game of chance, in the sense that the players cannot control what cards they are dealt, but also one of skill. The principal skill lies in bluffing, in covering up one's disadvantages and pretending to the other players that one holds better cards than is actually the case. Although Blanche is excluded from the poker game, this is a powerful metaphor for the way in which she lives and for how she conducts her relationship with Mitch. Stanley, being a more serious poker-player than Mitch, sees through her bluff more quickly.

The poker games also symbolize Stanley's masculine dominance. He often goes out bowling and drinking with his friends, but he is not the type of hen-pecked husband who is chased out of the domestic space. On the contrary, he rules the roost and takes over the apartment for himself and his friends whenever he feels like it, sending his wife and her sister outside or into the apartment's peripheral space.

The significance of the two poker games in the play is that they both give Stanley an opportunity to influence how Mitch thinks about Blanche. When Stanley tells Mitch,

Get y'r ass off the table, Mitch. Nothing belongs on a poker table but cards, chips and whiskey.

he also presages that he intends to lay his so-called cards on the table and tell all he knows or surmises about Blanche, thus sullying Mitch’s feelings for her. Mitch metaphorically lays his cards on the table during the poker game, telling the other players that he worries about his sick mother and that, moreover, when she dies, he will be all alone. He is not married, as the other men are.

Blanche tries to interject herself into the game, saying that she finds poker “so fascinating.” Her goal seems apparent. She has heard Mitch say that he is single and lonely, and she is interested in getting to know him.

The poker game also serves as a device to show how undignified Stanley’s treatment of his wife is when he slaps her on her thigh in front of the other men. Eventually, Stella shouts to the other men to leave if they have “one spark of decency” so that her family blowup can occur in private.

Stella even says,

When men are drinking and playing poker anything can happen. It's always a powder-keg.

The significance of the two poker games in Tennessee Williams's A Streetcar Named Desire plays off of the idea of juxtaposition. Juxtaposition is a literary device which places two or more things near one another in order to illustrate a contrast.

The first poker scene appears early in the play. Stanley and his friends are playing poker, and Stella and Blanche are out (so as not to disturb the men and their games). The ladies do not stay out long enough for the poker game to end. Blanche does not know any of the men except Stanley, and she falls into her flirtatious persona. She tries to draw attention to herself by changing in front of a backlit curtain, through which the men can see. She flirts with Mitch and questions Stella about Mitch's background. Eventually, the ladies anger Stanley to the point of eruption; he throws a stereo out of a window and hits Stella. Stella flees the flat, and Blanche follows her. Stanley ends up being thrown into the shower by the other men in an effort to shock him out of his drunken rage.

The second poker game happens at the very end of the play. Blanche is showering and getting ready to leave the flat. Although she thinks that she is going on vacation with an ex-"beau," she is being taken to a mental hospital. In the previous scene, Stanley has raped her, and Stella cannot believe Blanche and go on living with Stanley. Stella decides to believe her husband and sends Blanche to a mental hospital.

The juxtapositions the scenes illuminate are the changes in the characters. Blanche is no longer the flirtatious woman in a search for love. Stella is no longer a woman enamored with her "perfect" husband. Stanley, though, is the same man he was at the beginning. This lack of a change in Stanley accentuates his inability to identify his own shortcomings and change them for his wife and child. His static nature proves to be incapable of the necessary change in order to deal with the world around him. The poker games illuminate Stanley's lack of ability to change, while also illuminating the dramatic changes in both Stella and Blanche.

Two aspects come to mind:

1) The aspect of luck, fortune and destiny: One underlying theme of "A Streetcar Named Desire" is that people are sometimes arbitrarily subjected to hardship, such as when Blanche and Stella's family lose their home "Belle Reve." Hand-in-hand with this idea, though, is counter statement that people can take charge of their lives and are not necessarily at the mercy of fate (as Blanche often supposes).

2)The leit motif of deception and appearance versus reality: Blanche puts a lot of emphasis on putting forth a good image and making things seem better than they really are. This is certainly a mechanism of defence, but it keeps her from dealing with her problems. Instead she puts on "a poker face" until she talks more honestly with Mitch in the end.