Haka haka what? Team USA won against New Zealand in the FIBA Basketball World Cup in Spain, on Tuesday, Sept. 2, but their victory is not what's making the viral news rounds.

In a pre-game ritual, the New Zealand players (known as the "Tall Blacks") performed the haka — a traditional Maori dance featuring synchronized movement and war cries. As they performed the ancient ritual with convincing ferocity, their opponents could not help but be baffled by what they were watching.

Cameras zoomed on U.S. players like former NBA MVP Derrick Rose, James Harden, and Kenneth Faried, all of whom appeared mystified, stunned, and utterly confused by the spectacle.

After his team's 98-71 victory, U.S. coach Mike Krzyzewski told the Associated Press that his players were told in advance about the ritual. "We actually were going to shake hands with them afterwards," Coach K said. "We knew that that was a really neat thing to do and it's part of their tradition, and we admire that."

Watch the funny clip above!