When the Washington Capitals are at their best, the mistakes are minimal. It’s required precision for the patient, defensive-oriented and low-scoring type of game they want to play. But when things go awry, as they did in the third period of Game 1 against the New York Rangers, it’s difficult to climb back.

From a miscommunication on a line change, a failed attempt to retrieve the puck and lost coverage assignments, the miscues piled up and led to a pair of Rangers goals 90 seconds apart that the Capitals wouldn’t overcome in a 3-1 defeat to open up this Eastern Conference semifinal series.

“One mistake, two mistakes cost us a goal, cost us a game,” said Alex Ovechkin, who recorded just one shot on goal in 21:03 of ice time. “We have to play much better and we have to step up in different level. It’s unfortunate that we lost, but again, everybody knows it’s only one game and [Game 2 Monday] is going to be different game. It’s going to be new day and we have to regroup and stay tight.”

Throughout the first round against the Boston Bruins, Washington was largely able to limit its errors. When it didn’t rookie netminder Braden Holtby bailed them out. On Saturday Holtby (11 saves) openly admitted that he didn’t have an acceptable performance, and that he had a tough time engaging in the contest seeing as New York fired only 14 shots against him. The Capitals’ defensive hiccups, though, are equally responsible for the tallies.

Washington entered the final frame of regulation in a familiar place, tied 1-1 after goals by Artem Anisimov and Jason Chimera in the second. With just more than 13 minutes remaining in the frame, Alexander Semin took a point shot on Henrik Lundqvist (17 saves) that the netminder directed into the corner. With the play seemingly deep in the New York zone, defenseman Mike Green went to the bench for a change.

The play didn’t remain there, though. Instead, the puck rolled along the boards and up the left wall, where Derek Stepan beat Marcus Johansson to it and sent a pass to rookie Chris Kreider in the neutral zone. By the time Green scrambled back to the play, the Rangers rookie had fired a shot that put New York ahead 2-1.

Green, who was a team-low minus-2 in 21:45 of ice time, said nobody came on to change for him.

“We thought he was going to keep it in and he was trying to make a change and got caught up ice,” Coach Dale Hunter said. “Every game is a game of mistakes out there. . . . Just part of hockey.”

Two shifts later, the Rangers struck again when top center Brad Richards was afforded far too much time and space along the goal line.

Chimera and defenseman Karl Alzner both pursued Kreider along the left side boards in the Capitals’ zone, so that when the puck popped free to Richards he was left unguarded. The veteran pivot was allowed to skate toward the net alone and thread a shot past Holtby before any other Capital was even a stick length away from him.

While Hunter didn’t want to place blame on his 22-year-old goaltender, who was critical to Washington reaching the second round, Holtby took a harsh view of his own outing and said the two third-period tallies were shots he could have stopped.

“Obviously I wasn’t real happy with it. It was a tough game, mentally wise, and I didn’t do a good enough job tonight,” Holtby said. “Just crucial parts of the game. Those goals in the third, those are goals that I’d like to have back. But you can just tell. When you have a few low shots in the game, you usually know that there’s not a flow. We weren’t making crisp plays and whatnot. That’s what happened tonight.”

There was an unevenness to the Capitals’ game as they plodded along in this sometimes excruciatingly slow-moving contest, but in addition to the mistakes there was one noticeable change in tenor from the previous series. After trailing for only 24:23 in seven games against Boston, by the conclusion of one outing against the Rangers, Washington had trailed for 20:18.

“I think in Boston maybe we spent a little too much time in our defensive zone. Today I think it bit us in the butt,” Chimera said. “I think we got to take care of the puck. But there’s a Game 2 coming up pretty soon.”