Toews recorded his first four-point game this season as the Blackhawks claimed their third straight victory and improved to 7-1-1 since February 24 when leading scorer Patrick Kane broke his collarbone against Florida.
The Islanders have now suffered four successive defeats ??? their worst run of the season ??? and have scored only one goal during that streak.
They are also now five points behind the Atlantic Division-leading New York Rangers, who have played four fewer games.
PK Subban scored the last of the Montreal Canadiens’ three second-period goals and Jacob De La Rose had a goal and an assist as they won for just the third time in nine games by beating Florida 3-2.
Dustin Tokarski made 41 saves in his first start in six games and the Canadiens remain top of the Atlantic Division with 95 points, two points ahead of Tampa Bay.
In Newark, Cory Schneider made 35 saves in earning his fifth shutout of the season for the New Jersey Devils as they beat Pittsburgh 2-0 to win for the ninth time in their last 14 games and keep their faint playoff hopes alive.
Jacob Josefson scored in the second period and Adam Henrique added an empty netter with 49 seconds to go.
Alex Steen scored two goals and Brian Elliott made 25 saves for St Louis as they eased past Calgary 4-0 to win for the fifth time in six games and move one point clear of Nashville in the Central Division.
The Blues are in a three-way tie for first overall in the NHL with the Anaheim Ducks and New York Rangers.
Calgary tumbled out of a Western Conference playoff spot after Winnipeg beat San Jose 5-2.
Ottawa’s Andrew Hammond (11-0-1) made 35 saves in a 2-1 overtime win over Carolina to become the second goalie in NHL history to allow two goals or fewer in his first 12 starts, matching the record set by Boston’s Frank Brimsek who also went 12 consecutive games in 1938 without giving up more than two goals.
Mark Stone scored the winning goal 4:46 into overtime for the Senators who are 12-1-1 since a 6-3 home loss to the Hurricanes on February 16.
Boston Bruins 1-2 Buffalo Sabres (after shootout)
Calgary Flames 0-4 St Louis Blues
Carolina Hurricanes 1-2 Ottawa Senators (after overtime)
Chicago Blackhawks 4-1 New York Islanders
Florida Panthers 2-3 Montreal Canadiens
Nashville Predators 2-3 Minnesota Wild (after overtime)
New Jersey Devils 2-0 Pittsburgh Penguins
Vancouver Canucks 4-1 Philadelphia Flyers 1
Winnipeg Jets 5-2 San Jose Sharks