Tkachuk sustained a cut to his hand during Wednesday’s practice, and left the ice to get stitched up.
Flames head coach Glen Gulutzan said the injury is “not concerning,” and listed the 18-year-old as day-to-day.
“He’s just not going to be able to play, with where the stitch is,” Gulutzan told reporters. “He’s going to be day-to-day.”
Kris Versteeg and Lance Bouma will also miss Thursday’s game. The club recalled Hunter Shinkaruk on the weekend and Linden Vey on Thursday to help fill the void.
Tkachuk, who was officially kept past the 10-game mark by the NHL club as of a week ago, has three goals and six points in a dozen games this season.