PITTSBURGH - Kimmo Timonen called Monday's win in Boston "desperation."

You can call last night's drubbing in Pittsburgh a lack of perspiration.

Last night, the Flyers played about as desperate as a team that already has tee times booked for the second week in April. That is to say that the Flyers played without any of the fire or fervor that enabled them to beat one of the league's hottest teams just 24 hours earlier.

"Right now, we're not playing with enough heart to have success," Flyers captain Mike Richards admitted.

As a result, the Flyers had their doors blown off by the defending Stanley Cup champion Penguins, 6-1, and waddled out of Pittsburgh with their tails between their legs.

They wrapped up a three-game road trip with an unfulfilling 1-2 record, sandwiching two of their most putrid performances of this drab season around an inspiring victory on Monday that seemed like it would propel the Flyers back on course.

"It's really disturbing," Flyers coach Peter Laviolette said. "We took a small step forward and a big step backward. We didn't compete."

The Flyers have dropped 11 out of their last 14 games and sit a full 16 points behind Pittsburgh in the Atlantic Division race. They are now in a five-way tie for 14th place (second to last) in the Eastern Conference.

Sidney Crosby gave the Flyers their first punch to the gut just 3:30 into the nationally televised game when he deposited an errant Pittsburgh rebound behind a sprawling Brian Boucher.

It was Crosby's 21st goal of the season and his 21st goal in 28 regular-season games against the Flyers. He also added two assists.

"We put ourselves in the hole right off the get-go," forward Danny Briere said. "We can't be doing that, especially against a team like Pittsburgh. A team like Pittsburgh is going to hurt you."

Three different Flyers - Arron Asham, Riley Cote and Dan Carcillo - fought Pittsburgh players in a 16-second span following Crosby's goal, but none seemed to rile the Flyers. Just 36 seconds after Carcillo's resounding pounding of Craig Adams, Bill Guerin's simple tap-in gave the Penguins a 2-0 edge.

Carcillo, playing on the first line with Richards and Jeff Carter, was one of the few bright spots for the Flyers. He scored their only goal of the game 5 minutes later on the power play to make it 2-1 with 8 minutes remaining in the first period.

"I can't speak for anyone else, but I'm trying to get to the net and score," Carcillo said.

That was the problem. After Jordan Staal's backbreaking shorthanded goal for Pittsburgh 3 minutes later, the Flyers collapsed. They were cooked after not even 15 minutes had elapsed.

Odd-man break after break left Boucher, who struggled with rebounds in his sixth consecutive start, out to dry.

"It's been like a shooting gallery at times," Chris Pronger said. "He's got to scramble from side to side to side to side. It's difficult as a goaltender to control your rebounds. We've got to give him a little more help back there."

"We had some mental lapses where they created a lot and turned into goals," Richards explained. "It seems like everyone was reluctant to do the right things. It just seems like a lot of the plays are mental mistakes."

The Flyers failed to capitalize on five more power-play opportunities as Pittsburgh began to pile up the goals. Staal added another in the second while Ruslan Fedotenko's and Evgeni Malkin's third-period tallies were just salt in the wound.

Carcillo had another power-play goal disallowed just 2 minutes into the final frame that would've made it a 4-2 game. His hunger for rebounds around the net was lost on teammates - even though the game was already lost.

"We're passing up a lot of opportunities," Laviolette said. "We're still looking for something better out there."

At this point, Flyers general manager Paul Holmgren may be looking for someone better out there. Briere insisted that the Flyers know the shoe could drop after each brutal loss.

"We're smart enough. We know what's at stake," Briere said. "If you don't understand after a coach gets fired, you're never going to understand."

Nearly halfway into the season, it's not a stretch to wonder if they ever will.

Leighton snagged

The Flyers claimed goaltender Michael Leighton off re-entry waivers from Carolina.

Leighton, 28, was not in uniform for the Flyers last night in Pittsburgh. He was slated to join the team today in Voorhees, N.J., where it is expected that Johan Backlund will be loaned back to Adirondack. Backlund is in his first North American pro season.

Leighton is expected to serve as Brian Boucher's backup until Ray Emery can return from abdominal surgery in late January.

Leighton played four games for the Flyers in 2006-07 and also played for Flyers coach Peter Laviolette in Carolina. In 76 total NHL games, he has a 3.10 GAA and .896 save percentage.

"It's a fresh start for him," Laviolette said. "We added a veteran goaltender, even though it's not by words a veteran of the National Hockey League, he's played a lot of years in the American Hockey League. He was a top goaltender down there."

"He's an experienced guy in the NHL right now," Paul Holmgren said. "He strengthens our goaltending and our organization right now."

The Flyers will split his $600,000 salary cap hit with Carolina. The move comes just 4 days after the Flyers signed veteran John Grahame to a tryout contract with the Phantoms.

Holmgren reiterated last night that Grahame was only signed to play in the AHL. A Flyers team source told the Daily News last night, though, that had the Flyers not nabbed Leighton, Grahame would have been in the NHL by Saturday.

For more news and analysis, read Frank Seravalli's blog, Frequent Flyers, at http://go.philly.com/frequentflyers.