If you trust your eyes, the Flyers have swung this series and seized control from the Chicago Blackhawks. If you believe your eyes, the impossible now seems more than possible.

The Flyers are two wins from the Stanley Cup.

So are the Blackhawks, of course. This is where you can't be sure of your eyes. Have the Flyers solved Chicago and goaltender Antti Niemi as completely as it appeared in Friday night's 5-3 victory? Or are we being fooled by home-ice mirages?

A few days ago, Chicago fans and media were gloating about how certain the Blackhawks were to close out the Flyers and win their first Cup in 49 years. After two games at the United Center - which came on the heels of a sweep of San Jose - the Blackhawks were looking pretty good.

After two games at the Wachovia Center, we can be sure of two things: This is now a best-of-three series. And if the Flyers were prohibitive underdogs at the start of the Finals, only a fool would call them that as the series heads back to Chicago for Game 5 Sunday night.

For three breathtaking games, these two teams were almost never separated by more than a goal. The Blackhawks scratched out wins at home. The Flyers needed overtime to get back into the series in Game 3.

But some trends favored the Flyers, and they blossomed into full flower in Game 4.

The Flyers dominated the Blackhawks in the third periods of Games 2 and 3. In Game 2, that may have been a result of the Flyers needing to score to catch up while Chicago sat back trying to protect its lead. That was certainly the dynamic Friday night, as the Blackhawks furiously fought back from a 4-1 deficit.

But in Game 3, it looked more as if the Flyers were wearing Chicago down. That certainly appeared to be the case in an overtime that saw the Flyers score twice (sort of).

Logic says that if the Flyers could wear the Blackhawks down in each game, they could wear them down as the series dragged on. Game 4 was a compelling argument to that effect.

The Flyers controlled the game from the start. There's a reason the TV cameras and the referees caught the Blackhawks slashing helplessly at the backs of Flyers' legs. They were behind the play and frustrated.

The Blackhawks picked up a pair of penalties in the first five minutes. Andrew Ladd, dressing for the first time in the series, took all of 36 seconds to pick up a high-sticking penalty. Four minutes later, Tomas Kopecky went off for the same thing.

Five seconds after that came the moment that really should concern Chicago. Mike Richards swooped down on defenseman Niklas Hjalmarsson behind the net, picked his pocket and the puck, then fired a backhand shot that beat Niemi.

Not only did the Flyers have the all-important first goal, they got it from their captain. Richards and his line had been shut down through three games. After coming up big again and again to get his team to the Finals, Richards was worrisomely absent from the score sheet.

Ten minutes later, off another turnover by Hjalmarsson, Matt Carle fired the puck into an empty net. For the first time in the series, the Flyers had a two-goal lead.

Their third goal, though, was even more telling. Chicago's Patrick Sharp had redirected a blast from the point past Michael Leighton with less than 90 seconds left in the first period. Within a minute, the Flyers restored their two-goal lead on a play that should deeply concern the Blackhawks. It suggested that, as Peter Laviolette suggested in a crafty bit of gamesmanship, Niemi was feeling the pressure.

The play started off harmlessly enough. Scott Hartnell, whose turnover led to Sharp's goal, had the puck in the Chicago zone. He wheeled and passed it back to Kimmo Timonen at the point. Timonen cruised toward the goal and Niemi, for some reason, came way out of his net.

He left the whole thing open for Claude Giroux, the overtime hero of Game 3. Timonen feathered a pass, and Giroux scored the easiest goal of his life.

Meanwhile, at the other end, the Flyers got their best game yet from Leighton. He had no chance on Sharp's goal. The two third-period goals were hardly his fault, either. One was scored on a 5-on-3 advantage, the other caromed off sticks and skates as Jonathan Toews and Timonen skated into the crease at high speed.

Leighton is getting stronger, Niemi weaker. The Flyers seem to be getting stronger, the Blackhawks struggling with the pressure.

Is it all a mirage, caused by home ice?

The best-of-three Finals will decide.