Doncic played through the thumb ailment during Friday night's loss to the Miami Heat but said after the game that he had problems catching the basketball.
"I didn't know how important the thumb was to hold the ball," Doncic said. "It was tough. ... I wasn't myself [Friday]. Just have to learn from that and move on."
"It was pretty clear in the Miami game that it's really a problem still," Carlisle said. "He'll be out today, and tomorrow we'll see where we are."
Doncic, who was selected to his first All-Star Game this year, has averaged 28.6 points, 9.4 rebounds and 8.8 assists per game this season. The 21-year-old swingman leads the Mavs in all three categories.
The Mavericks are also without guard Jalen Brunson (right shoulder sprain), center Willie Cauley-Stein (personal reasons) and big man Dwight Powell (right Achilles surgery) against the T-Wolves, according to the team. Carlisle said Cauley-Stein will rejoin the team in Chicago.