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Nike probing Zion Williamson shoe malfunction that led to injury

DURHAM, NORTH CAROLINA - FEBRUARY 20: A detailed view of the shoe worn by Zion Williamson #1 of the Duke Blue Devils against the North Carolina Tar Heels during their game at Cameron Indoor Stadium on February 20, 2019 in Durham, North Carolina. (Photo by Streeter Lecka/Getty Images)

NEW YORK — Nike says it's investigating why Duke freshman Zion Williamson split a shoe open during a game against rival North Carolina. But the sportswear giant says it's an "isolated occurrence."

The Beaverton, Oregon-based company says it's concerned and says quality and performance of its products are of "utmost importance."

The shoe malfunction, which forced Williamson to leave the game with a knee sprain, happened in front of a crowd of celebrities, including former President Barack Obama and Spike Lee.

DURHAM, NORTH CAROLINA - FEBRUARY 20: (EDITORS NOTE: Retransmission with alternate crop.) Zion Williamson #1 of the Duke Blue Devils reacts after falling as his shoe breaks in the first half of the game against the North Carolina Tar Heels at Cameron Indoor Stadium on February 20, 2019 in Durham, North Carolina. (Photo by Streeter Lecka/Getty Images)

Williamson's left shoe fell apart as he planted hard near the free throw line. The blue rubber sole ripped loose from the white shoe from the heel to the toes along the outside edge, with Williamson's foot coming all the way through the large gap.

Nike quickly became the target of ridicule on social media, which presents challenges for the sportswear brand.

DURHAM, NORTH CAROLINA - FEBRUARY 20: Zion Williamson #1 of the Duke Blue Devils walks off the court after falling as his shoe breaks against Luke Maye #32 of the North Carolina Tar Heels during their game at Cameron Indoor Stadium on February 20, 2019 in Durham, North Carolina. (Photo by Streeter Lecka/Getty Images)

Nike's shares are down 1 percent, or 84 cents, to $84 in early morning trading Thursday.

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