A game of tic-tac-toe between two Indiana Pacers fans went viral -- as an example of how not to play the children's game.

The fans were chosen from the audience Wednesday night, when the Pacers played the Milwaukee Bucks, to participate in a simple game of tic-tac-toe with a basketball theme: The participants had to shoot and make a basket before being able to move a piece on the board, with the game's winner receiving a prize.

One player, however, didn't seem to grasp the game.

Though things started out well for the two men -- both making layups and putting their pieces on the board to try and get three in a row -- the game went awry when one player had the chance to win...but instead put his marker on a different spot.

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“The first one to put it down wins! What are you going to do?” the announcer said, assuming the player would make the obvious, winning move. He did not.

Later, the other player had a chance to win -- but he, too, decided to choose another spot.

“What are you doing?!” the announcer yelled incredulously.

In the end, the game was a tie.

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The Indiana Pacers shared video of the mind-boggling match on Twitter, adding the descriptor: “When you don’t know how to play tic-tac-toe.”

Former NBA star Shaquille O’Neal sympathized with the confused contestants, however.

“Tic Tac Toe is hard…,” O’Neal tweeted with a laughing emoji.