Down 4-1 late in the second period, Crosby got into the second fight of his career -- going after Brett McLean right off the faceoff deep in Florida's end.
Just a few minutes after he was penalized for a scrum with Gregory Campbell, Crosby was given 19 minutes in penalties for fighting, unsportsmanlike conduct and an instigator.
"I asked him to go, and he said yes. And usually, yes means yes," said Crosby, who fought Boston's Andrew Ference last season. "I mean, I wouldn't have wasted 20 minutes in the box for that. I guess he didn't take me serious. I don't know, it wasn't worth 20 minutes, though, that's for sure."
Ville Peltonen, Bryan McCabe, Richard Zednik and Michael Frolik also scored and Keith Ballard, Cory Stillman, Nick Boynton and Stephen Weiss each had two assists for Florida, which pulled within three points of the Penguins for eighth place in the Eastern Conference standings.
"It was a huge game... I couldn't have scripted anything better," Panthers coach Peter DeBoer said. "It's hopefully what the doctor ordered for us."
Pittsburgh entered the game having lost five of seven and had been anticipating that facing the struggling Panthers would reverse that trend.
Now having lost six of eight, Crosby's frustration grew after gaining only four points in that time.
Crosby threw his gloves off and grabbed an apparently unsuspecting McLean, who was kneeling over to take the faceoff. McLean eventually was able to drop his gloves and attempted a few swings but did not connect. His nose was bleeding as he left the ice, but that apparently was just due to the breaking open of a scab when he fell to the ice.
Crosby's punches were more directed at McLean's shoulders as he tried to take McLean's jersey off.
McLean, who said he did not hear Crosby ask him for a fight, took the incident in stride.
"Everybody can kind of understand what he's doing for their team there," McLean said. "He's their leader."
DeBoer also was complimentary of Crosby's actions, but Panthers alternate captain McCabe was not so forgiving of the league's young superstar, calling him "unprofessional" and "embarrassing."
"You don't jump a guy while his head's down taking a faceoff," the veteran defenseman said. "That's pretty immature and childish.
"That's not what the game needs, you know what I mean? But whatever. We beat them where it counted, and that's all that matters. We needed those points."
The Panthers scored on four of their first 10 shots -- including two on only five first-period shots against Pittsburgh's Marc-Andre Fleury.
That prompted Pittsburgh coach Michel Therrien to pull Fleury, but Florida scored on its first shot against backup Dany Sabourin -- and tallied three against him on 12 second-period shots before Fleury returned for the third.
"Goaltending is a big part of today's game, and both those guys didn't do the job," Therrien said.
Peltonen's fifth of the season opened the scoring -- on a wrist shot from the left point with Fleury leaning the wrong way.
Late in the first, Horton's ninth came on a partial breakaway, his wrist shot beating Fleury to the stick side.
After Fedotenko gave Pittsburgh its only score with an unassisted goal at 1:37 of the second, McCabe (his seventh of the season) and Zednik (fifth) scored power-play goals 2:21 apart midway through the period, and Horton scored on a breakaway during 4-on-4 play 90 seconds after Crosby and McLean fought.
Frolik made it 6-1 when he scored on a delayed Penguins' penalty call 4:14 into the third.
"I think they were really frustrated," Horton said, "And that's what we needed. That's what we wanted. I think it was better for us that they did get frustrated. It kind of tilted the game in our favor."
Crosby entered the game with 30 penalty minutes this season. ... Penguins C Tyler Kennedy played for the first time since Dec. 3. He had been out with a sprained knee. ... Pittsburgh was 0-for-3 on the power play, extending the team's streak to 24 consecutive unsuccessful power plays over the past six games. ... The previous time Pittsburgh lost by as many as five at Mellon Arena was Feb. 2, 2006, to Ottawa.