Updated

Alexander Semin had a goal and set up Jay Beagle's go-ahead score Saturday, lifting the Washington Capitals to a 4-3 win over the Boston Bruins.

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 and is now in sole possession of eighth place in the Eastern Conference. Washington also trails Florida by one point in the Southeast Division.

Brooks Laich and Matt Hendricks also scored, and Tomas Vokoun stopped 30 shots for the Capitals.

Brad Marchand, Milan Lucic and Johnny Boychuk scored for Boston, which failed to extend its winning streak to three games for the first time since late December.

Tim Thomas, playing in his eighth consecutive game, made 26 saves for the Bruins.

Washington improved to 20-0-0 when it leads after two periods.

Boston tied the game on Marchand's goal 4:58 into the second before the Capitals scored twice over the final 8:38 to take 4-2 edge into the third.

Seconds after the Bruins killed off Greg Zanon's holding penalty, the Capitals kept the pressure on and Beagle scored on wrister in the slot off a pass from Semin.

They made it 4-2 on Laich's power-play score late in the period when he redirected former Bruins defenseman Dennis Wideman's shot by Thomas from the slot.

Mike Knuble misfired on a chance to give the Capitals a three-goal lead. He hit a post with just over 7 minutes to play.

Boychuk then cut it to 4-3 when he came charging in to score off a rebound with 3:13 left in the third, scoring in his second straight game after not getting a goal since Dec. 3.

The Bruins pulled Thomas for an extra skater with 1:20 to play and Washington held on despite a pair of chances on scrambles in front.

Marchand tied it at 2-all when he collected a loose puck at center ice after Jordan Caron checked Alex Ovechkin into the boards, sending the puck free. He skated in alone, waited and slipped a shot between Vokoun's pads.

The Capitals scored a pair of goals 25 seconds apart in the opening period to grab a 2-0 lead. Semin collected the rebound of Karl Alzner's shot right in front and slipped a shot behind Thomas at 7:50 of the period.

On the ensuing shift, Troy Brouwer tipped Dmitry Orlov's shot from the point and the puck caromed over to Hendricks, who fired a shot into a wide-open net at 8:15.

The Bruins called timeout after the second goal and controlled play for the rest of the period, cutting it to 2-1 when Lucic slipped a short wrist shot between Vokoun's pads off a faceoff with 5.6 seconds left in the first.

Boston outshot Washington 10-1 after the timeout.

But, that did little to help the Bruins in the second period. The Capitals took over following Marchand's tying goal, outshooting Boston 12-4 for the rest of the period.

Washington posted a 15-7 edge in shots on goal in the second and scored twice, collecting eight of its shots on power plays.

NOTES: Injured Bruins G Tuukka Rask, out 4 to 6 weeks with a lower abdomen/groin strain groin suffered last Saturday, said before the game that it's "probably closer to six weeks than four. That would be right around playoff time and I think we're going to shoot for that, and hopefully it's better by that time." ... Vokoun started his second straight game. ... Boston LW Benoit Pouliot was a late scratch with what the team announced as a "lower body injury" early in the second period. ... Lucic has two goals, five assists in his past six games. ... The Capitals host Toronto on Sunday before a five-game road trip. ... Boston plays at Pittsburgh Sunday.