It was Gustafsson’s fourth goal in two games, after Saturday’s hat trick against Toronto, a game that ended 5-2 to Washington.
David Perron gave Detroit the lead in the first period, followed by 2-0 by Oskar Sundqvist on the power play, played behind the goal line by Jonatan Berggren.
But Washington both reduced and equalized in the second period when Nic Dowd scored twice in 11 seconds.
After Detroit regained the lead in the third period, Gustafsson stepped forward and tied the score at 3–3. The game was decided with 22 seconds left in overtime, when Washington’s Marcus Johansson played Dmitrij Orlov.
Washington has now won seven of its last eight games.
In the meeting between Boston and Florida, Linus Ullmark managed to stop 37 pucks thrown at him.
Boston took the lead by scoring three goals in five minutes and 16 seconds in the first period. After another Boston goal, Florida rallied in the second period and scored three goals in five minutes and 20 seconds.
But Ullmark recovered in the third period and Boston had extended the lead to 7–3 by the end of the game. Patrice Bergeron scored the game’s last two goals.
Boston coach Jim Montgomery praised the Swedish goalkeeper’s performance after the game and says that in the third period he was like a wall in the goal.