Lars Eller, Dmitry Orlov, Andre Burakovsky, Nicklas Backstrom and John Carlson also scored for the Capitals, who broke open a tie game by scoring four unanswered goals in a 38-minute span between the first and third periods.
Washington goalie Philipp Grubauer made 35 saves. Evgeny Kuznetsov had three assists while Backstrom and Orlov had two assists apiece.
Brock Nelson and Andrew Ladd scored in the first period and Ryan Pulock added a goal in the third for the last-place Islanders. Tanner Fritz logged two assists.
Starting New York goalie Christopher Gibson was pulled after stopping seven of 12 shots. Jaroslav Halak recorded eight saves on nine shots in relief.
Nelson opened the scoring at 2:19 of a wild first period, when he took Fritz's wraparound pass and fired a shot over Grubauer's left leg.
Eller tied the score with 9:28 remaining in the first, as his shot from the left faceoff circle went past a screened Gibson. Oshie put the Capitals ahead 57 seconds later, when he took a pass from Burakovsky and fired the puck over a falling Gibson.
The Islanders tied the game exactly a minute later, when Ladd took a pass from Mathew Barzal and beat Grubauer under his glove hand for his first goal since Dec. 21. However, the Capitals regained the lead at 3-2 on Orlov's tip-in of Evgeny Kuznetsov's shot into the crease with 2:43 left before the first intermission.
Burakovsky redirected Jakub Jerabek's shot from the blue line past a screened Gibson 3:12 into the second for a 4-2 advantage. The Capitals chased Gibson with 9:38 left in the second, when a bouncing puck in the crease ticked off the leg of Backstrom and into the net.
Carlson scored with 4:19 left in the third. Pulock scored 52 seconds later, and Oshie added an empty-netter with 1:54 remaining.
--Field Level Media
Washington | NY Islanders | |
Nicklas Backstrom 3 | Points | Ryan Pulock 2 |
T.J. Oshie 2 | Goals | Ryan Pulock 1 |
Evgeny Kuznetsov 3 | Assists | Tanner Fritz 2 |
Nicklas Backstrom 1 | Power Play Goals | N/A |
N/A | Short Handed Goals | N/A |
Philipp Grubauer .921 | Save Percentage | Jaroslav Halak .889 |
Philipp Grubauer 35 | Saves | Jaroslav Halak 8 |
Team | Shots | Goals | Power Play | Penalty Kill | Penalty Mins | Face Offs Won |
Washington | 22 | 7 | 1-1 | 3-3 | 6 | 30 |
NY Islanders | 38 | 3 | 0-3 | 0-1 | 2 | 32 |