Just 2:01 after Scott Hartnell snapped a 13-game goal drought to tie the game, Claude Giroux flipped a spectacular saucer pass to a driving Pronger, who tipped the puck over Cristobal Huet's right pad for his ninth of the season.
"I think (Giroux) saw me early on when I was crossing the blue line that I was going wide," Pronger said. "He was trying to get it somewhere near me where I can whack at it toward the net. He made a great pass, it landed flat and I was able to get it up over his pad."
After a scoreless 40 minutes that featured strong play by Huet and Philadelphia's Michael Leighton, the game turned wide-open in the third.
Philadelphia's Simon Gagne started the scoring just 1:18 in, but Kris Versteeg and Marian Hossa answered to put the Blackhawks in position to win for the fourth time in their last five games.
That's when the much-maligned Hartnell stepped up. Taking a 130-foot slap pass from Kimmo Timonen at the Chicago blue line, he used his body to hold off Brent Sopel and shoot the puck over Huet's blocker.
"I just tried to protect the puck," Hartnell said. "I didn't want to make a move because the guy was right on me. I was able to get it over his pad and get it in."
The goal was his 13th of the season but first since Jan. 30. That's a huge drop-off for a player who had a career-best 30 last season.
"It seems like it's been forever since I contributed," Hartnell said. "I think with about 10 minutes to go there, before they scored their second goal, I thought, 'Jeez, it's going to be another game without a goal.' You think negative thoughts when you're slumping."
Hartnell is one of the more popular players on the team, so an uplifting moment became even more significant because of the goal-scorer. Switched off Jeff Carter's line to play with Giroux and Danny Briere, Hartnell had a team-high four shots in 14:34 of ice time.
"I liked his jump," coach Peter Laviolette said. "He was moving, working to get the puck. He had the goal and just an overall strong game."
"All of a sudden it was 2-2, then 3-2, and I didn't even know what happened there at the end but we can't be giving that up, especially in the last minute of the game." -- Kris Versteeg
Gagne also has reason to feel happy, as his goal was his seventh in the last 10 games. Daniel Carcillo pounced on Brent Seabrook's giveaway, carried the puck behind the net and tried for a wraparound, but his shot went through the crease. Gagne, in the left circle, scored his 13th of the season into a mostly empty net.
The lead didn't last long. Moments after an apparent Jonathan Toews goal was waved off for having come after a whistle, Versteeg converted a Hossa rebound for his 16th of the season.
The score stayed tied until Hossa's 20th of the season put the Blackhawks ahead at 12:51. Troy Brouwer did a great job holding off Lukas Krajicek to maintain possession of the puck in the middle of the ice and send a pass to Hossa in the right circle. Leighton had no chance on Hossa's laser beam past his blocker.
The Blackhawks looked ready to roll into Sunday's nationally-televised game with the Capitals with a victory, but things changed in a hurry.
"Yeah, I mean it was like bang-bang-bang," Versteeg said. "All of a sudden it was 2-2, then 3-2, and I didn't even know what happened there at the end but we can't be giving that up, especially in the last minute of the game."
Contact Adam Kimelman at email@example.com