The Washington Capitals, poised to open a four-game trip Saturday in Detroit, gave themselves a sweet going-away present Friday night to start a back-to-back. With the Capitals down two goals to the Tampa Bay Lightning to start the third period, Jakub Vrana and Alex Ovechkin scored to force overtime before Dmitry Orlov sent the Capital One Arena crowd home smiling with a blast from the left faceoff circle for a 4-3 win.

The victory left the Capitals (18-4-5) tied with Boston with an NHL-best 41 points as they left the District on Friday for a trip that starts in Detroit and includes three games in California. They will travel knowing their special teams are clicking and few deficits are too large to overcome. Washington is 4-3-1 when it trails after two periods.

“Sometimes when we get a little mad or when we get into the game physically and guys are skating, guys are forechecking, we kick it into a different gear,” T.J. Oshie said of the team’s strong third period. “It’s hard to play like that for a full 82 games, but it is nice to see when we need it, the guys are stepping up as a whole and getting the job done, find ways to climb back or find ways to hold leads.”

The Capitals twice rallied from two-goal deficits against Tampa Bay, a comeback fueled by a pair of power-play goals. They were down 2-0 and on the man advantage a little more than five minutes into the second period when Evgeny Kuznetsov redirected a cross-ice pass from Oshie to cut the lead in half.

Tampa Bay’s Alex Killorn restored the two-goal margin late in the second before the Capitals hit their stride in the third. Their rally started with a goal that few thought was actually in the net.

Jakub Vrana connected on a shot from the right circle at the 3:45 mark that beat goaltender Andrei Vasilevskiy on the short side. No one really made a move of acknowledgment except for Vrana, who skated to the corner and raised his hands in celebration. Moments later, the home crowd found its voice as the rest of the Capitals on the ice joined Vrana in celebrating.

“He’s a pretty good goalie,” Vrana said. “I didn’t know from the beginning how to put the puck through him, so honestly I was really happy that it went in.”

Midway through the period, Ovechkin beat Vasilevskiy on a power play, connecting from his favorite spot in the left circle. It was Ovechkin’s 17th goal of the season and the 675th of his remarkable career. One more number: It was his 255th tally on the power play, tying him with Teemu Selanne for third on the NHL’s all-time list.

The Capitals scored on both their power-play chances Friday after failing to light the lamp in their previous five chances.

“It was great to see especially the second unit out there making those plays under that pressure,” said goaltender Braden Holtby, who improved to 13-2-4.

Orlov completed the comeback during the wide-open extra period, taking a pass from Oshie (three assists) and driving to the circle before unleashing a snap shot past Vasilevskiy’s short side.

It was the 12th time Washington has reached overtime this season.

“I look for the pass first. . . . I think Vasilevskiy might have been cheating me on that shot, so I think that’s maybe why he gave up a goal to me,” Orlov said.

The Capitals’ penalty kill was also strong after entering the game tied for eighth in the NHL at 83.7 percent. The Lightning, which entered with the third-best power-play unit in the NHL, scored on its first chance when Brayden Point beat Holtby from between the circles off a crisp pass from Victor Hedman. But Tampa Bay’s next three chances with the man advantage were stymied.

“Especially the way they started against us, too, they were snapping pucks around and we were having a tough time,” Oshie said. “The PK did a good job, and they were making some adjustments. Some guys got some big blocks, and like always [Holtby] was great back there to keep the puck out of the net on the three that we stopped.”

Through the first quarter of the season, Capitals Coach Todd Reirden had preached the importance of limiting the amount of minor penalties. The Capitals came into Friday’s game tied for second in the NHL with 99 through 26 games.

And while the Capitals continue to take too many minor penalties, the penalty-kill unit got back crucial member Garnet Hathaway after his three-game “intent to injure” suspension for spitting on Anaheim’s Erik Gudbranson on Nov. 18.

With Hathaway back in the lineup next to Brendan Leipsic and Nic Dowd, it was the first time the team’s original fourth line was together since Nov. 13 in Philadelphia. Dowd hurt his hand that night and missed five games.

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