Blues 3, Blackhawks 2
Alex Steen found the net with 21.1 seconds left to lift the Blues to a narrow win over the Blackhawks.
The Blues (3-0-0) won their first three games for just the third time in the 47-year history of the franchise and the first time since the 1993-1994 season.
They never won four in a row to start a campaign.
Vladimir Tarasenko and David Backes also scored for the Blues while St. Louis goalie Jaroslav Halak made 26 saves.
Patrick Kane and Jonathan Toews scored for the Stanley Cup champion Blackhawks (1-1-1).
Flames 3, Canadiens 2
Calgary rookie Sean Monahan scored once and added an assist in a victory over the Montreal Canadiens.
Sven Baertschi and Curtis Glencross also scored for the Flames (2-0-2), who extended their point streak to four games.
Calgary goalie Joey MacDonald made 33 stops in his third consecutive start.
P.K. Subban and Lars Eller scored for the Canadiens (1-2-0).
Monahan, who turns 19 on Saturday and must be returned to the Ontario Hockey League's Ottawa 67's if he does not remain in the NHL has collected points in all four of Calgary's games so far and leads the team with three goals.