Josh Hart cut to the basket, and Jalen Brunson found him with a nice bounce pass.
But as Hart rose up, Celtics center Luke Kornet's left elbow found Hart's left eye.
Hart immediately went down, gushing blood out of his face.
The slightly graphic image can be seen here.
Hart almost immediately got a towel over his face and started getting treatment, but he didn't go far.
To be able to play the rest of the game, Hart had to stay in and shoot his free throws.
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The foul happened with 3:30 left in the first quarter with the Knicks trailing 21-16.
Hart got mostly cleaned up and stayed in the game for his foul shots with a large bandage above his left eye.
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