What is basket interference? Explaining controversial call on Karl-Anthony Towns in Timberwolves' loss to Mavericks

The Timberwolves and Mavericks delivered a thrilling start to the Western Conference Finals. But the ending of Game 1 did not come without its controversy.

Minnesota, trailing by two points with less than two minutes remaining, appeared to tie the game when Karl-Anthony Towns slammed home a putback dunk on a missed field goal attempt. But officials ruled basket interference and took the basket off the board.

Another opportunity to tie the game came on the next possession after a traveling call on Dallas' Dereck Lively, but Minnesota's Mike Conley turned the ball over. Luka Doncic buried a jumper to put the Mavericks up four with 49 seconds left, giving the team a comfortable advantage down the stretch.

Dallas went on to win, 108-105, after Conley intentionally missed a free throw at the end of the game with the aim of setting up a 3-point shot for another Timberwolves player. The ball did not get back to one of his teammates in time for Minnesota to get a shot up.

Why was a basket interference penalty called on Towns? Here's what you need to know.

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What is basket interference?

Basket interference is another word for goaltending. The rule is most often called against defensive players attempting to block a shot. But it can be called against offensive players, as in this case.

Officials, even upon further review, deemed that the initial shot from Minnesota still had a chance to score, which brought Towns' putback attempt into conflict with the following aspect of the rule:

Touch any ball from within the playing area when it is above the basket ring and within the imaginary cylinder.

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Offensive goaltending is rarely called. The shot Wednesday appeared to be leaving area of the rim, though it could have had a chance to hit the rim again on the way down, making it a close call for the referees.

Towns had plenty of other opportunities to score in the game. He went 6-for-20 in the Game 1 defeat, including just 2-for-9 from 3-point range, and finished with 16 points, seven rebounds and two assists.