Montreal had not won at Florida since Dec. 28, 2018.
"We understand the caliber of team we were playing," St. Louis said. "But this wasn't just a win, but how we got it. I thought we played a smart, calculated game."
The Panthers, who have been shut out four times in their past eight games, next play the New York Rangers on Monday.
"I don’t think we are going to dwell on this one, just kind of move on," forward Sam Bennett said. "Mistakes are going to be made; it's about how you help each other and fix them. We are just going to move on from this game."
NOTES: Dobes is the seventh goalie in NHL history to defeat the defending Stanley Cup champions in his debut, and the first since Reto Berra of the Calgary Flames against the Chicago Blackhawks on Nov. 3, 2013. Dobes also joined John Gibson of the Anaheim Ducks as the only active goalies to have a shutout in his NHL debut (minimum one game played this season). … Caufield has 12 goals on the road this season, tied for third in the NHL behind Sam Reinhart of the Panthers (14) and Brayden Point of the Lightning (13).