MONTREAL—Montreal interim coach Dominique Ducharme tested positive for the coronavirus and missed the Canadiens’ 3–2 overtime victory Friday night in Game 3 of the semifinal series against the Vegas Golden Knights. The NHL said Ducharme received a confirmed positive COVID-19 test nine days since receiving his second vaccine dose. No other Canadiens players or members of the Vegas Golden Knights have tested positive. Ducharme isolated immediately. General manager Marc Bergevin said he doesn’t know how long Ducharme will be out. “I’ve talked to Dom twice today—he’s doing fine,” Bergevin said. “He’s at home. As far as how long he’s going to be out, we’re dealing with and talking to Health Quebec and also NHL protocols. It’s an ongoing situation, so I can’t tell you how long.” Assistant Luke Richardson ran Montreal’s bench in Game 3 with assistants Alex Burrows and Sean Burke. “As of this morning, (Ducharme) was in contact …