Chicago's defensemen looked incredibly slow and surprisingly out of sync in the team's 102d game of the season. Meanwhile, Antti Niemi, brilliant through most of the playoffs, was far from the spectacular puck-stopper whose play helped fuel the Blackhawks' drive to the Stanley Cup Finals.

That combination against a hungrier and more aggressive Flyers squad spelled a 5-3 defeat for Chicago in Game 4 Friday night at the Wachovia Center, and likely left coach Joel Quenneville searching for fixes on the plane trip back to the Windy City.

"I know the series is wide open," Quenneville said. "We have to take advantage of home ice. We played well there all year. I still think we have to be smart, disciplined, and make them play defense."

In the first period, Niemi let three of eight shots escape him and light the lamp. But he was not alone in blame. The Blackhawks allowed the Flyers to skate down loose pucks, stay too long in the offensive zone, and roam freely around the net.

On the Flyers' third goal, Claude Giroux, Game 3's overtime hero, was left all alone behind and to the right of Niemi. He accepted a nifty pass from Kimmo Timonen and easily stuffed home his 10th playoff goal.

Defensemen Niklas Hjalmarsson and Brent Sopel were on the ice for the first two goals. Sopel and Duncan Keith made up the last line in front of Niemi on Giroux's tally.

Mike Richards stripped Hjalmarsson behind the net and backhanded a shot past Niemi for the first score. Winger Tomas Kopecky had just gone off the ice for high-sticking Danny Briere in the back. The score gave the Flyers a 5-for-12 success rate on the power play in the series.

Another Hjalmarsson miscue, this time a weak clearing attempt, directly led to the Matt Carle score that made it 2-0 at the 14-minute, 48-second mark of the first period.

"A couple of plays there you would like to have back," Quenneville said. "You have to like and commend [Hjalmarsson] on how he's competed all year and how he plays. Some nights, some tough things can happen. But his character and his perseverance is what we look for. We look for him to bounce right back."

Chicago has struggled mightily on the power play. The Blackhawks were 0 for 8 in the series before Dave Bolland tipped home a Keith slapshot with 7:59 to play in the third period.

To win the now-deadlocked series, the Western Conference champions will have to get more out of center Jonathan Toews. The NHL's leading playoff scorer (27 points) has yet to score a goal and is minus-3.

His linemates, Patrick Kane (minus-4 Friday) and Dustin Byfuglien, have been quiet as well. Kane's lone goal came in Game 3. Byfuglien, held to one shot in the first two periods Friday, has only a Game 1 assist.

Patrick Sharp and Keith, who posted three assists and logged a team-high 23:26, each took five shots.

Blackhawks winger Andrew Ladd, scratched for the first three games because of an undisclosed upper-body injury, made his first appearance in the Finals. Just 36 seconds in, the 6-foot-2, 200-pounder was whistled for interference in front of the Chicago net.

Contact staff writer Rick O'Brien at 610-313-8019 or robrien@phillynews.com.