Ottawa’s Kyle Turris clears the puck past Washington’s MIke Green as the Capitals blow a 2-0 first-period lead and fall to 1-4-1, just one point out of the Eastern Conference cellar. (Jana Chytilova/Getty Images)

For 38 minutes on Tuesday night, the Washington Capitals put forth a complete demonstration of the game they want to play under Coach Adam Oates. They were relentless on the forecheck and dominated puck possession, creating a seemingly endless flow of scoring chances while rendering their opponent ineffective.

Momentum is a funny thing, though. A goal with 83 seconds remaining in the second period offered life for the Ottawa Senators, then a missed assignment off a faceoff early in the third allowed them to tie it and wrestle control of the contest.

Ottawa rallied from its two-goal deficit to capture a 3-2 win over the Capitals at Scotiabank Place, squashing the memory of the visitors’ strong start.

But as they churn forward in this compressed schedule, the Capitals don’t have time to dwell on what could have been and must focus on what they did well to keep progressing.

“It’s a tough one because when you play a really good hockey game you obviously want the win. When you have a 2-0 lead that should be enough in this league,” Oates said. “Of course you don’t want that result, but we played good hockey. We had a couple penalties in the offensive zone, which you don’t want, but I thought all in all we played a very good hockey game. You can’t fault effort or decisions and it’s a shame to lose.”

The Post Sports Live crew wonder whether there is a direct correlation between Alex Ovechkin’s individual goal-scoring and the Capitals’ wins and losses. (Post Sports Live)

The game winner came with 2 minutes 30 seconds remaining and Joel Ward in the box for high-sticking. Senators veteran defenseman Sergei Gonchar teed up a one-timer from the point that found its way through traffic and past Michal Neuvirth, who finished with 24 saves in his fourth consecutive start.

Gonchar’s tally wrapped up what began for the Senators late in the second period. Washington (1-4-1, three points) had dominated the start of the game, earning a 2-0 lead on goals by Troy Brouwer and Matt Hendricks in a strong first period. For as well as they played in the opening frame, however, the Capitals improved upon it in the second.

Washington spent almost the entire opening 15 minutes of the second period in the offensive zone.

The Capitals controlled play, forced successive turnovers and hardly allowed their foes to even consider crossing their own blue line for an extended period of time, eliciting boos from the home crowd. But Washington couldn’t find a way to beat Ottawa netminder Craig Anderson (31 saves) a third time.

An ill-timed cross checking penalty by Mathieu Perreault with just more than four minutes to go in the frame brought a barrage from the Senators but Washington withstood that push. It was on an unassuming rush up ice with 1:23 left in the second that Ottawa (4-1-1, nine) finally got on the scoreboard.

Racing down the right wing side, Erik Condra threw the puck toward the slot where it was deflected by Jim O’Brien past Neuvirth to make it 2-1. The goal didn’t just cut the lead in half, it gave Ottawa all-important life before the final break.

Oates and several players insisted the Capitals disregarded the late goal and entered the third period with every intention of repeating their early domination.

“We came in to the dressing room here with a lot of confidence. You never want to give up goals late in a period but I think we shrugged it off,” Brouwer said. In the third “we got hemmed in our zone for a couple shifts. We lost the momentum early on in the third period and weren’t able to get it back.”

The start of the third brought a more energized Senators squad. They started forcing turnovers, pushing the pace and causing Washington to scramble more in its own zone. The Capitals iced the puck, won the faceoff but then coughed up the puck again and after another unorganized series shot the puck into the netting, bringing a faceoff to the right of Neuvirth.

Nicklas Backstrom won the draw against Kyle Turris but winger Wojtek Wolski drifted toward him, leaving Milan Michalek with time and space. Michalek shot a backhander past Neuvirth to tie the game just 2:20 into the third. It was just the 16th shot he faced all game.

“It’s always tough when you’re not facing a lot of shots,” Neuvirth said. “It’s tough to stay focused but you know obviously I would like to have the second goal [back] but I thought we played good as a team and we’ve got to keep doing that.”