TAMPA — Alex Ovechkin was so excited he bent over, swung both arms and then raised them up, screaming all the while. The fans in blue at Amalie Arena started for the exits, but the Washington Capitals faithful in red made their appreciation known. “O-vi” chants echoed from the upper deck down to the lower bowl before the Tampa Bay Lightning supporters who were left answered with boos.

Smiling on the bench, Ovechkin cared not, having just joined an exclusive club. Ovechkin scored his 50th goal of the season Saturday night in the Capitals’ 6-3 win, becoming just the third player in NHL history with eight 50-goal campaigns — legends Wayne Gretzky and Mike Bossy are the other two. At 33, Ovechkin is just the fourth player to score at least 50 goals at this age or older.

“You always want to do something special, but sometimes it’s hard,” Ovechkin said. “I’m happy to get it done.”

He made it look easy, scoring his 51st goal less than two minutes later, an exclamation point on what had already been a memorable night for his team. The Capitals’ win over the Lightning was one of their most complete games of the season, a statement both to Tampa Bay and the rest of the league that they are again heating up at the right time and they still have skill in spades. Along with Ovechkin’s two goals, Nicklas Backstrom and T.J. Oshie also tallied two goals apiece. The win keeps Washington in first place in the Metropolitan Division with a three-point lead over the New York Islanders.

“I think we set the tone right away,” Ovechkin said. “We sent a message right away. All four lines played outstanding.”

A year ago, Ovechkin was three goals short of 50 entering Washington’s regular season finale, and though he scored twice in that game, the 50th tally eluded him. This one came with three games left — Ovechkin is on his best point-per-game pace since the lockout-shortened 2012-13 season. A long run to a first Stanley Cup last year meant more wear on his body and then a shorter summer to recover and prepare for this season. It was fair to wonder how motivated he would be after finally adding a championship to his résumé.

On Saturday night, with Ovechkin showing no signs of slowing down, the question shifted to how many more times he could score 50 goals in his career.

“You think I know?” he responded.

Asked to venture a guess, Ovechkin instead changed the subject to his team’s play building toward the postseason, indicative of what’s most important to him.

“I just enjoy my time,” Ovechkin said. “I just enjoy playing hockey obviously. . . . Now is the time to play smart, play the way we’re going to play in the playoffs and get ready for that.”

His teammates have been most impressed with how his two-way game has rounded out over the past year, and perhaps there was no better example of that than on a power play in the first period, when Tampa Bay’s Cedric Paquette had a shorthanded breakaway. Ovechkin chased Paquette down the ice, a furious backcheck to keep him from getting off a shot. Oshie then went on to score on that power play to make it a 3-0 game.

“It’s almost unfair that you just expect him to score 50 every year,” Oshie said. “But the little things that we notice is things like that. The backcheck, him on the forecheck getting hits, wearing down the other team’s [defensemen], blocking shots. Those are things that I think he’s done a great job of these last couple of years, and it’s turning him into a complete 200-foot player and we’re able to have him out there in those big moments and know he’s going to take care of us.”

Ovechkin’s milestone night came in the third and final tilt against the Lightning this regular season, a rematch of the Eastern Conference finals. For Tampa Bay’s final home game of the regular season, the Presidents’ Trophy was carried onto the ice for a brief ceremony commemorating the Lightning finishing with the NHL’s best regular season record. The Capitals stayed in the visiting locker room during the pregame festivities. They’re familiar with the trophy — they have won it three times in the past decade — and they also know that it doesn’t often translate into playoff success.

Washington hopes to repeat as Stanley Cup champions, and it expects that it will again have to get through Tampa Bay, and these three head-to-head meetings over the past two weeks have been as intense as they have been bruising. It all came to a head in the third period Saturday. Defenseman Brooks Orpik dropped the gloves with Tampa Bay’s Anthony Cirelli, and less than three minutes later, forward Tom Wilson dropped hulking Lightning defenseman Erik Cernak in another bout.

“Obviously, it’s a pretty heated rivalry now,” Wilson said. “We’ve played each other a lot over the last year. It’s inevitable when you’re playing them all the time and you have a hard playoff series. . . . It’s an emotional game. That’s a playoff-type game right there. It’s a fun time of year for that to happen.”

Just as the Lightning was making a push, cutting the Capitals’ lead to two goals in the third period, Ovechkin delivered one goal and then another. The stick he scored with was put aside, as was the puck he shot in, just another bit of history made. There could be more to come.

“He never surprises me with what he does,” Coach Todd Reirden said. “Every day it’s something different, and his energy level is at an all-time high this year. I think he’s really been a driving force for our team. . . . I’m hoping there’s many more 50-goal seasons.”

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