In his first season with the Canadiens, the 28-year-old Prust has proven extremely valuable with four goals, nine points and an NHL-leading 81 penalty minutes in 25 games.
Ryan White is expected to take Prust's spot in the lineup against Florida. The injury will snap Prust's streak of 223 consecutive games played, which was the longest among current Canadiens players. Prust had last missed a game Jan. 15, 2010.
Therrien also said Peter Budaj would be in net against the Panthers. Carey Price, who played against Tampa Bay on Saturday, was in net in the teams' first two meetings and allowed only one goal on 55 shots.
Price made 26 saves on Feb. 14 when the Canadiens beat the Panthers 1-0 in overtime at BB&T Center. Price stopped 28 shots in the Canadiens' 4-1 victory against Florida at Bell Centre on Jan. 22.
Jacob Markstrom is expected to get the start in net for the Panthers, who on Sunday reassigned forward Jon Rheault to the San Antonio Rampage of the American Hockey League.