It was the second straight win for the Capitals after a three-game losing streak (0-2-1).
Washington moved two points ahead of Winnipeg into sole possession of eighth place in the Eastern Conference. Washington also trails Florida by one point in the Southeast Division.
Brad Marchand, Milan Lucic and Johnny Boychuk scored for Boston, which failed to post its first three-game winning streak since late December. Tim Thomas, playing in his eighth consecutive game, made 26 saves.
AVALANCHE 3, OILERS 2, SO
Cody McLeod and Mueller added goals in regulation for the surging Avalanche, who kept within striking distance of eighth place in the Western Conference.
DEVILS 2, ISLANDERS 1
But Clarkson tied it with 1:39 remaining, squeezing the puck past Nilsson for his 28th goal, and Zidlicky quickly gave the Devils the lead with a power-play tally.
New Jersey (39-24-5), which won two of three from the Islanders this week, has three consecutive victories and wins in four of five. The Devils are 4-1-1 in their last six games and have allowed one goal or fewer in five straight games. They outscored the Islanders 7-2 in their two wins this week.
FLYERS 1, MAPLE LEAFS 0, SO
Bryzgalov made his 11th straight start, and his biggest save came on Phil Kessel's breakaway in overtime. He also denied Kessel in the shootout.
Jonas Gustavsson made 27 saves for the Maple Leafs, who have dropped seven straight home games. Gustavsson got credit for his fourth shutout this season.
Toronto is six points behind the eighth-place Capitals in the Eastern Conference heading into Sunday's game at Washington.
HURRICANES 4, LIGHTNING 2
Skinner gave Carolina a 3-2 lead when he skated around the net and scored from a tough angle at 6:36 of the third period. Chad LaRose added an empty-net goal.
Ward stopped all 18 shots he faced in the second period. He made two strong saves on NHL goals leader Steven Stamkos, including a spinning shot by the center from the low left circle.
The Lightning, who started a seven-game homestand, got goals from Ryan Malone and Nate Thompson. Tampa Bay dropped five points behind eighth-place Washington in the Eastern Conference playoff race. Carolina trails the Capitals by seven points.
SABRES 4, SENATORS 3, SO
OTTAWA (AP) - Tyler Ennis scored in regulation and then added the winning goal in the shootout to give Buffalo a victory over Ottawa.
The Senators were short-handed for the final 67 seconds of overtime after Karlsson took a tripping penalty. Bishop made two great saves to force the game to a shootout.
STARS 2, DUCKS 0
DALLAS (AP) - Brenden Morrow scored a power-play goal in his return from an 18-game injury absence, Kari Lehtonen made 21 saves for his 20th NHL shutout, and Dallas stretched its winning streak to five games with a victory over Anaheim.
Morrow, the Stars' captain, had been out with neck and shoulder stiffness. He scored his ninth goal of the season at 2:37 of the second period. Morrow registered his 514th career point, tying him with Jere Lehtinen for ninth in franchise history.
Lehtonen made the goal stand up, preserving his third shutout of the season with a sharp glove save against Saku Koivu with under 15 minutes to play.
Michael Ryder added an empty-netter, tying a career high with his 30th goal. The Pacific Division-leading Stars are 9-0-1 in their last 10 games. Dallas won the season series from the Ducks 5-1.
Jonas Hiller made 21 saves for Anaheim, 2-5 in its last seven games.
BLUES 4, BLUE JACKETS 1
ST. LOUIS (AP) - Brian Elliott made 21 saves and St. Louis beat Columbus to tie a franchise record with its 29th home victory of the season.
St. Louis is an NHL-best 29-4-4 at home with four games left. The Blues went 29-7-4 at home in 1980-81.
St. Louis, 44-18-7 overall for a league-leading 95 points, has won four in a row and eight of nine.
Elliott, who backed up Jaroslav Halak the last three games, lowered his NHL-best goals-against average to 1.61. The Blues have allowed just one goal in each of the last four games and two or fewer in nine straight.
Cam Atkinson scored for Columbus. The Blue Jackets had won four straight.
PREDATORS 3, RED WINGS 2
NASHVILLE, Tenn. (AP) - Andrei Kostitsyn was assisted by his brother, Sergei, on a pair of power-play goals to lead Nashville over Detroit.
COYOTES 3, SHARKS 0
Raffi Torres added his 12th goal of the season early in the third period for Phoenix, which ended a five-game losing streak. The Coyotes have 78 points and are in seventh place in the Western Conference.
Smith earned his 16th career shutout, and the fifth this season. Smith's previous shutout was Feb. 16 against the Kings.
Antti Niemi made 26 saves for San Jose, which has lost five straight and seven of eight. The Sharks have 75 points and trail eighth-place Colorado by one point in the West.
CANADIENS 4, CANUCKS 1
VANCOUVER, British Columbia (AP) - Erik Cole scored two third-period goals, and Montreal beat Vancouver for its first winning streak in a month.
Cole gave Montreal a 2-1 lead 13 seconds into the third period. He made it 4-1 with 8:58 left, knocking in his own rebound for his 25th goal of the season and third in four games.
P.K. Subban had a power-play goal, and Blake Geoffrion netted his first tally of the season for the injury-plagued Canadiens, who outshot Vancouver 30-18 over the final two periods. It was the third win in 10 games for Montreal (27-32-10).
The last time the Canadiens - the last-place team in the Eastern Conference - strung wins together was a four-game streak that ended Feb. 11 with a 5-0 victory at Toronto.
Ryan Kesler gave the Canucks a 1-0 lead in the second period. Vancouver (42-19-8) has lost three of the first games of its seven-game homestand. The Canucks trail Western Conference-leading St. Louis Blues by three points.