Troy Brouwer delivers a punishing check to Chicago’s Brent Seabrook in the first period, but it was the Capitals who absorbed the loss on a night in which the Stanley Cup banner was raised in Chicago. (Nam Y. Huh/Associated Press)

For a half-hour, the Washington Capitals waited in the visitors’ dressing room here at United Center for the conclusion of a ceremony that they hope one day to host themselves.

They waited for the defending Stanley Cup champions to revel in their victory one last time with a display of LED lights that flickered along with the music as a banner was raised to the rafters before they could kick off a new NHL season. But when the Capitals finally took to the ice, they were reminded why the Chicago Blackhawks won that title.

Mikhail Grabovski recorded a hat trick and four points in his debut, but an inability to protect the lead and a failed five-on-three late in the third period negated those efforts. Washington fell, 6-4, to the Blackhawks in its season opener Tuesday night after succumbing to the style of game its opponent thrives on.

“We blew a lead. We fought so hard to get the lead, and then we let it get away, but they’re the champs for a reason,” Coach Adam Oates said. “They’re a really good hockey team, and it’s hard to play that way. You don’t want to trade chances. You don’t want to trade opportunities with them. That’s more their style and not ours.”

The teams alternated goals — Brandon Bollig and Patrick Kane for the Blackhawks and Grabovski and Alex Ovechkin for Washington — until the third period, which Chicago entered with a 3-2 lead and seemingly strong control of the game after taking advantage of numerous Capitals turnovers at even strength.

The Post Sports Live crew offers bold predictions for the Capitals season, which opens Tuesday night in Chicago against the Blackhawks. (Post Sports Live/The Washington Post)

A pair of power plays in the first five minutes were just what Washington needed to find its way back into the game, though. The Capitals’ three core players teamed up for a setup when Nicklas Backstrom won a faceoff back to Ovechkin, who faked a shot before passing over to Mike Green. The defenseman slid over from where he received the puck just enough to alter his angle and fired a wrister that Grabovski tipped at the top of the crease to beat Blackhawks goalie Corey Crawford.

Grabovski’s third goal of the night came on a redirect as well. He deflected another of Green’s shots in front to give the Capitals their first lead of the game at 4-3 with only 5 minutes 16 seconds gone in the third. But the Blackhawks aren’t a team that backs down from a battle of offensive firepower.

“I was just a little bit kind of lucky,” Grabovski said. “Just right spot where I’m supposed to be and great shot for Green.”

Less than three minutes after Washington captured the lead, Connor Carrick gave the puck away as he entered the offensive zone and sent Brandon Saad racing in the opposite direction. A give-and-go with Michal Handzus allowed Saad to race toward the crease, beating both John Erskine and Carrick to the net for a backhander that erased the Capitals’ progress to make it 4-4.

Chicago’s decisive goal didn’t come on an especially pretty play or the result of a power play but rather was a fluky shot by defenseman Johnny Oduya that squeaked past the glove of netminder Braden Holtby as it made its way low across the ice.

“It was a rolling puck,” said Holtby, who stopped 29 of the 34 shots he faced. “I knew it was going to be kind of a knuckler, but it kind of just sunk out of my sight. I don’t know why. I have to watch on the replay why. It just completely fooled me.”

The Capitals received a perfect opportunity to regain the advantage with less than four minutes remaining in regulation when Chicago rookie Joakim Nordstrom fired the puck over the glass while the Caps were already on a power play, giving them a five-on-three for 1:26.

Washington’s power play, which scored on three of its first four attempts, came up empty when it mattered most. The unit recorded four shots on goal, but Crawford (28 saves) was stellar in keeping the Capitals at bay.

“I saw him make a couple good saves and I saw a couple of one-timers that got blocked,” Oates said. “I think in a sense they got lucky because [the blocked shots] went in the stands. Sometimes when a guy blocks a shot it stays on the ice. That helps the power play because now they’re moving around. Whereas a guy blocks a shot and it happens to go in the stands, they get to reset, and we have to win a draw again. That hurt us a little bit.”

Long before the failed five-on-three or Marian Hossa’s insurance goal, awarded when he was pulled down by Green while en route to an empty net, the Capitals were getting swept up in playing Chicago’s game.

More worrisome than the goals themselves was the abundance of turnovers. Chicago’s offense is difficult to contend with when you don’t lose the puck to keep their possessions alive and present quality scoring chances. Offering help like turnovers at the blue line that lead to breakaways or blind clearing attempts that are easily picked off makes trying to escape one’s own zone a Herculean task.

“We were turning it over too much, trying to make too many cute plays. And you watch them play, and that’s kind of how they play, but they seemed to execute a lot more than we did tonight at least,” Karl Alzner said. “I think part of it had to do with playing against them, you’re trying to do little things like that as well because clearly it works. We want to do that, we just have to get better at it I think.”