Per Mark Berman of the New York Post, Ntilikina has been ruled out for the remainder of the game with a sprained left ankle.
The injury occurred one minute after the second-year guard came into the game. He grabbed one rebound before departing.
Ntilikina's injury adds to what has been a difficult season. Entering Friday, the 20-year-old was averaging 6.2 points and 2.6 assists over 34 games. His 34.9 shooting percentage ranked 418th out of 477 players in the NBA.
The Knicks surprised many when they selected Ntilikina with the eighth overall selection in the 2017 draft instead of Dennis Smith Jr.
The decision raised even more eyebrows less than a week later, when the team and then-president Phil Jackson mutually agreed to part ways. Ntilikina's fit with the triangle offense was one of the selling points of his selection, and the triangle went out the door with Jackson.
Ntilikina eventually became a key contributor as a reserve. He averaged 5.9 points and 3.2 assists per game as a rookie, and New York allowed 6.7 more points per 100 possessions when he went to the bench in 2017-18, per NBA.com.
Knicks head coach David Fizdale has taken a tough love approach with the team's younger players, including Ntilikina. At one point, he benched the French international for three straight games to send a message.
Should Ntilikina miss more time because of injury, Fizdale will likely use Trey Burke as his primary backup.