Detroit defeated Chicago 6-4 during the second U.S. Winter Classic game in front of 40,818 raucous fans. ((Nam Y. Huh/Associated Press))

Already garnering rave reviews for its Winter Classic contest, the NHL received more good news when the New Year's Day event on NBC earned a ratings increase of 12 per cent.

The game between the Detroit Red Wings and Chicago Blackhawks at Wrigley Field on Thursday drew an overnight rating of 2.9 and a 6.0 share, the best showing for the league in almost 13 years.

Detroit defeated Chicago 6-4 in the second U.S. outdoor game in front of 40,818 raucous fans. 

Last year's Winter Classic at the Buffalo Bills' Ralph Wilson Stadium drew a 2.6 overnight rating and a 5.0 share on NBC as the Pittsburgh Penguins edged the Sabres 2-1 in a shootout.

"Year one was an extraordinary experience," NBC Sports president Ken Schanzer said Saturday. "Year two was the establishment of what promises to be a great tradition."

The rating is the percentage watching a program among homes with televisions, and the share is the percentage tuned into the broadcast among those households with TVs on at the time.

Overnight ratings measure the 55 largest TV markets in the United States, covering nearly 70 per cent of the country. Each overnight rating point represents about 735,000 TV homes.

The NHL earned glowing reviews for its Jan. 1, 2008 game in Buffalo.

An estimated crowd of 72,000 braved snowy conditions to attend the contest, which drew robust television ratings in both the U.S. and Canada.

With files from the Associated Press