Golden State Warriors guard Stephen Curry has been ruled out indefinitely with a knee injury.
Curry limped off court during the third quarter of the Warriors' 119-113 win over the Dallas Mavericks after clashing knees with an opponent.
He had an MRI on Sunday which confirmed he had suffered "partial tears" to ligaments in his left knee, as well as bruising to his lower leg.
Curry, 34, will miss Monday's game against the Oklahoma City Thunder.
In a statement, the Warriors said "additional clarity on a potential timeline will be established in the coming days".
He could also miss out on a ninth appearance in the NBA All-Star Game on 19 February, for which he had been voted in as a starter.
Four-time NBA champion Curry had already missed 11 games this season with a partially dislocated shoulder.
Irving set for Dallas trade?
Meanwhile, the Brooklyn Nets have reportedly reached a deal to trade Kyrie Irving to the Dallas Mavericks.
The 30-year-old point guard had requested a trade after failing to agree a new contract, according to multiple reports.
Irving, selected as an NBA All-Star for an eighth time, has endured a number of off-court issues during his time in Brooklyn.
His decision not to get the Covid-19 vaccine meant he could not play in the Nets' home games during the 2021-22 season until March because of New York's ban on unvaccinated people in indoor venues.
He would later say his decision not to get vaccinated cost him a four-year contract worth $100m.
In November, Irving was suspended for eight games and had to apologise after posting a social media link to a film with anti-Semitic material.
BBC