Fans began streaming toward the Verizon Center exits with about eight minutes remaining, unable to watch the Capitals buckle yet again in an important game on home ice.

Sure, there have been clutch triumphs during the Alex Ovechkin Era on F Street. The Southeast Division-clinching victory over Florida in 2008 is a signature moment. Sergei Fedorov’s Game 7 winner against the Rangers a year later is another.

But Tuesday’s 5-1 setback against the Sabres was reminiscent of all the disappointments. The lopsided Game 7 loss to the Penguins in 2009. Games 5 and 7 vs. Montreal the following spring.

At one point in the third period Tuesday, one fan’s frustration boiled over when he screamed from the upper deck, “Hey [expletives], you want to make the playoffs?”

Of course they do. The question now is whether they can.

Presented with a chance to seize control of their own postseason destiny, the Capitals blew it and must rely on Buffalo or Ottawa losing – even if they were to win each of their remaining five games. (Florida’s shootout win over Montreal, meantime, pushed the Panthers’ lead to five points, so they can pretty much forget about hanging a fifth consecutive Southeast Division banner.)

Like those previous failures in big games, a lack of desire wasn’t the culprit against the Sabres.

It was the inability of this team’s core group to execute in the clutch. Yet again.

They out-shot the Sabres (45-31), doubled them up in hits (26-13) and dominated the visitors in the faceoff circle, winning 62 percent of the draws.

But that’s where the Capitals’ advantage ended.

Buffalo feasted on mistakes, buried pucks in the net and benefitted from timely saves by Ryan Miller, who is 4-0-0 with 0.75 goals against average and .977 save percentage in his last four starts.

At the other end, prospect Braden Holtby, pressed into service because of an injury to Tomas Vokoun and the pedestrian performance of Michal Neuvirth, misplayed the puck behind the net early in the first period, passing it to Sabres fourth liner Brad Boyes instead of defenseman Jeff Schultz.

Braden Holtby skates away from the Sabres celebrating their second goal of the first period. (John McDonnell/The Washington Post)

On the Sabres’ second goal, Holtby made the first stop but poked the puck into the slot. His rebound control wasn’t ideal. But where was Holtby’s help? Drew Stafford didn’t get one uncontested swipe at the puck, he got two. That’s on the defensive coverage (or lack thereof).

In the second period, the Capitals were trailing 3-1 when Ovechkin got his best chance to extend his scoring streak to seven games. He forced a turnover, then made a scintillating toe-drag in the circle but he was unable to beat Miller from point-blank range.

The game remained in reach deep into the second period. That, however, is when Ovechkin committed an inexcusable gaffe and Sabres blew it open. Ovechkin coughed up the puck at the blue line, then got outmuscled in the ensuing puck battle along the boards by Jason Pominville, whose shorthanded strike secured the two points. Ovechkin is 6-3, 230 pounds; Pominville is 6-0, 185.

It’s a game of mistakes. But it’s a rare night in the NHL, particularly in March, when a team can withstand freebies handed out by its goalie and best player.

“This mistake probably cost us the game,” Ovechkin said.

Despite the loss, the mood in the Capitals’ dressing room afterward was even-keeled and resolute.

“People were throwing around the term Game 7; it’s not,” Mike Knuble said. “There’s a tomorrow and there’s games after that. It’s not over. You have five more games to play.”

Laich pointed to the last-to-first run in 2007-08 as proof that it can be done.

“We’ve done it before,” he said. “It’s probably going to come down to the last game of the regular season. All that matters is you get in. …These next five games are going to tell the story of our hockey team.”

And whether it’s mentally tough enough, as currently constructed, to succeed when the season is on the line.    

More on the Capitals:
Washington stumbles in key game vs. Buffalo
Nicklas Backstrom passes baseline test
Caps’ playoff picture gets dicey after loss