Washington Capitals goalie Tomas Vokoun cools off during a break in the action. (Jonathan Newton/WASHINGTON POST)

After a week of emotional games against rivals to kick off the 2011-12 NHL season, the Washington Capitals faced an opponent of a different sort Saturday night in the Ottawa Senators.

Projected to struggle in a rebuilding year, Ottawa entered Verizon Center on Saturday with one win but hardly let the Capitals steamroll them into submission. Washington weathered a sloppy second period riddled with turnovers and defensive miscues to clinch a 2-1 victory, its first in regulation this season.

The Capitals are one of only two teams, along with Detroit, that boast a 4-0 record. While these early triumphs haven’t been completely sound 60-minute outings, Coach Bruce Boudreau doesn’t mind winning ugly as long as the Capitals keep improving.

“If we thought we were king of the world right now it’d probably be a little more difficult” to improve, Boudreau said. “Not every game, you’re not going to be beautiful, the other team wants to win, too. . . . We’re not satisfied, but we’re happy with some of the things, that people are getting better day in and day out.”

Tomas Vokoun put together another strong outing, finishing with 33 saves and shining when Ottawa (1-4) surged. He made 26 stops in the final 40 minutes, including saves on a breakaway against Milan Michalek in the third period and a one-timer from Daniel Alfredsson with less than two minutes remaining.

Capitals left wing Matt Hendricks and Ottawa Senators left wing Colin Greening collide and crash into the goal. (Jonathan Newton/WASHINGTON POST)

It was a more tense setting with time ticking away than many might have predicted against the Senators, but one that reflected the Capitals’ early imperfections regardless of their record.

In the first period, Washington controlled the pace and took advantage of Ottawa’s unimpressive penalty kill (68 percent) when Nicklas Backstrom scored his first goal of the season on a backdoor play, beating backup netminder Alex Auld (24 saves) to make it 1-0. Shortly after the 12-minute mark, Marcus Johansson scored on a pretty wraparound play to make it 2-0, and the Capitals appeared to be in control.

Everything seemed to be going along nicely for Washington, but after a strong start against a weak team, its lead was halved after a defensive breakdown. Only 25.2 seconds remained in the first period when Peter Regin scored on a play in which nearly every Washington player missed an assignment in the defensive zone.

“It’s been only four games but the neutral zone, the defensive zone, it’s the biggest problem right now that I see,” said Capitals defenseman Roman Hamrlik, who appeared in his 1,315th career NHL game to set a record for Czech-born players.

That lapse seemed to carry over to the second period, which Ottawa controlled. More than 10 minutes in, the Senators held an 8-2 advantage in shots, were creating odd-man rushes and kept catching Washington off balance and out of position in its own zone. But for each chance Ottawa created, Vokoun “stood tall,” according to Boudreau.

“I suspected it was going to be a really tough game,” Vokoun said. “I have been on that side [of a team not expected to perform well] before, what they were going through. . . . It was a tough game, it wasn’t any easier than Pittsburgh or Tampa. It just shows you this league. . . . They’re like playing a totally different team than what their record shows.”

Although the Senators didn’t even score in the second, it was an undeniably ugly stretch for Washington. The Capitals withstood the push and came out in the third with more life, finding offensive opportunities again. While they yielded 14 shots, they managed to give Vokoun more support than they did earlier.

The key for the Capitals now, players say, is to learn from their hiccups and letdowns to improve and not rest simply because they acquired two points.

“I think a lot of things can get better, obviously,” Backstrom said. “We keep talking about it in the locker room after the games and stuff. I think pretty much everything: Get quicker puck movement, better forechecks and better backchecks in the defensive zone, too. I think a little bit of everything and we’ll get better.”

Capitals notes: Jay Beagle did not face the Senators after being knocked out in a fight by Arron Asham in Pittsburgh on Thursday. . . .

Goaltender Michal Nevurith was scratched for a second straight game with an undisclosed lower-body injury. Neuvirth, who was seen limping and not putting weight on his right foot at Verizon Center on Saturday, took shots after the morning skate but was not made available to reporters.