Thompson played through the injury, finishing with 21 points on 8-22 FG. Until now, Thompson had only missed one game this season.
Though the Warriors are calling it a right thumb sprain, an ESPN report referred to it a fracture.
Unlike Curry, Thompson doesn't have a history of injuries.
The Warriors, now second in the West, are pretty banged-up at the moment.
Thompson hasn't missed more than five games since becoming a full-time starter during the 2012-13 season. Curry is averaging 26.3 points, 6.2 assists, and 5.1 rebounds while shooting 42.4 percent from downtown.
With the Golden State Warriors now chasing the Houston Rockets for the first seed in the Western Conference, they understand that every game is important for them to win, to give them a better shot at finishing the regular season on top of their conference and guaranteeing home court advantage throughout the playoffs.