BOSTON -- It's tough to determine who is more excited about the NHL's third Winter Classic, to be held Friday in Boston's historic Fenway Park: hockey-loving fans or National Hockey league officials who have visions of green dancing in their heads in anticipation of huge ticket sales and TV ad revenues.

The 1 p.m. game between the Boston Bruins and the Philadelphia Flyers will be held outdoors before hundreds of excited fans who have shelled out a collective $8 million for the privilege of seeing their favorite teams compete in the frosty open air.

Why all the fuss? NHL officials dreamed up the Winter Classic three years ago as a way to drum up interest in the sport and draw bigger advertising dollars. The first game was played in the Buffalo Bills stadium in 2008, and the second, between the Chicago Blackhawks and Detroit Red Wings at Wrigley Field, was played in January 2009 to rave reviews.

TV sponsors said they made good money off the Wrigley event and big money is what the event is all about.

Millions of dollars are being exchanged between the league, the Fenway Group and the Bruins over rink rental fees, the costs associated with building the rink and use of its refrigeration system, and rink rental costs for most of the past month for college games and to community groups.

Overall, however, the Winter Classic is a money-maker, the NHL's chief operating officer John Collins has said, and it's in no small measure because it's also a TV hit. Last year, 4.4 million viewers tuned in to the game, making it the most-viewed regular-season N.H.L. game in 34 years, according to the New York Times.