The team says it is going to offer another update before Game 3 of the NHL semifinal from the Vegas Golden Knights on Friday night at the Bell Centre.
The Canadiens say Ducharme will undergo further tests before the match. The group says Ducharme received his second dose of COVID-19 vaccine on June 9.
The Canadiens and Golden Knights are tied 1-1 in the best-of-seven series after Montreal got a break at Vegas with a 3-2 win in Game 2.
Ducharme was promoted to interim head coach from assistant following the shooting of Claude Julien on Feb. 24.
Beneath Ducharme, the Canadiens ended fourth in the all-Canadian North Division before upsetting Toronto and Winnipeg from the first two playoff rounds.
The Golden Knights have already seen this scenario play out in this postseason. Colorado Avalanche coach Jared Bednar missed a morning skate because of a COVID-19 testing irregularity. He was then cleared to coach in Game 6 of the second-round show against Vegas.