The New York Knicks will have to complete their Texas swing without their rising swingman.
Barrett left the game at the 1:36 mark of the first quarter and never returned. He logged his first scoreless game of the season, missing his single attempt and had one assist.
Before the injury, Barrett was ascending after a slow start to the season. Over his past 10 games entering Tuesday night, Barrett averaged 25.0 points, 6.2 rebounds and 3.2 assists while shooting 47.1 percent from the field and 44.6 percent from deep.
The Knicks will continue their Texas road trip in San Antonio on Thursday and Houston on Saturday to end the year. Then they will start the new year with a pair of home games against Phoenix Suns on Jan. 2 and a rematch with the Spurs on Jan. 4.
After Barrett went down with the injury, Thibodeau stuck with an eight-man rotation.
Quentin Grimes, who had a career-high 33 points against the Mavericks, had to continue stepping up if the Knicks want to snap their four-game slide.
It is unclear if Thibodeau will bring back one of Cam Reddish and Evan Fournier to the rotation if Barrett misses a significant time.
Follow this writer on Twitter: @alderalmo