Michael Ryder also scored for the Bruins, who improved to 38-8-6.
"As a team lately, we've come together and we've been playing quite well as a group defensively," Wideman said.
The Bruins have played outstanding defense all season in front of goalies Tim Thomas and Manny Fernandez. They've allowed just 114 goals, fewest in the league. Thomas made 14 of his 25 saves in the first period against the Flyers.
"Timmy was great in the net, and our D and forwards are doing a great job getting back and keeping teams to the outside," Wideman said. "That's something that we stress a lot. If a team is going to take a shot, make sure that they are taking it from the outside. I think we did a pretty good job at that and we limited their quality scoring chances."
The Flyers have lost five of eight games to drop to sixth in the Eastern Conference after a brief stay atop the Atlantic Division.
"There's a reason they're the best team in the league," Flyers coach John Stevens said. "They have a very committed team, they don't take a lot of chances and they have gifted offensive players committed to the checking game."
Krejci won a faceoff, dropped a pass to Shane Hnidy, and redirected his wrist shot past goalie Martin Biron to give the Bruins a 2-1 lead 5:48 into the third period.
Wideman made it 3-1 when his shot went through a screen and bounced off Flyers forward Jeff Carter's skate before trickling in.
"Every night it seems that somebody else comes up big and gives us a big lift," Bruins coach Claude Julien said. "We have a lot of different guys stepping up and that's allowed us to be competitive and be consistent."
Thomas, who leads the league in save percentage, made an outstanding, diving stop on Carter's side-angle shot in the first period. He made a glove save on Hartnell on a breakaway to preserve the tie in the second.
Ryder gave the Bruins a 1-0 lead on a redirection of Wideman's slap shot. Hartnell scored just 2:17 later to tie it. Joffrey Lupul set up the goal with a perfect crossing pass.
"They showed why they're a first-place team," Lupul said.
The Philadelphia Phantoms, the Flyers' AHL affiliate since 1996, were sold Wednesday to a Pittsburgh-based group. The Phantoms weren't going to have a home next season because the Spectrum will be torn down this year. It's unknown where the Flyers' top minor league team will play in 2009-10, though it's likely to be in Pennsylvania. ... The Bruins are 7-0-3 against Atlantic Division opponents. They're 9-1-2 in the last 12 games. ... Biron has lost his last four starts.
Copyright by STATS LLC and The Associated Press
Arena: Wells Fargo Center Location: Philadelphia, Pennsylvania
Referees: Mike Leggo, Brad Meier Linesmen: Steve Barton, Greg Devorski
Attendance: 19,748 (101.3% full)
Team Stat Comparison
Power Play Goals
Power Play Opportunities
Shots on Goal
No scoring this period
Michael Ryder (19)
Assists: Dennis Wideman, David Krejci
Scott Hartnell (19)
Assists: Joffrey Lupul, Ryan Parent
David Krejci (19)
Assist: Shane Hnidy
Dennis Wideman (12)
Assists: Blake Wheeler, Andrew Ference