Boosted by "Sunday Night Football - the nation's most watched program - singing contest "The Voice" and futuristic new drama "Revolution," NBC was up 12 percent in the younger age group prized by advertisers, compared to the 2011 TV premiere week.

According to Nielsen data, NBC was third in average total viewers (8.2 million), with long-time leader CBS finishing top of the pile so far in the new season with 10.7 million. NBC however said it was the only one of the four main TV networks to increase its average viewers over the same week in 2011, recording a 9 percent gain.

NBC, which is majority-owned by Comcast, has struggled with shrinking audiences since the end of 1990s hit comedies like "Friends," and "Frasier".

In a bid to rise from its perennial bottom place, the network ordered an unprecedented 16 news shows for the 2012-13 TV season, and is introducing six of them - mostly comedies - this fall.

NBC said that its new comedy "Go On", starring former "Friends" star Matthew Perry, was the No. 2 new comedy with 18-49 year olds.

"Revolution", was the top new drama series in that age group.

NBC's tactics of moving singing contest "The Voice" to a twice yearly cycle also appears to be paying dividends. The show has beaten its revamped Fox rival "The X Factor" despite the arrival of Britney Spears on its judging panel.

NBC used its broadcasts of the London Olympics in July and August to promote its new offerings, running early previews and offering several comedies online ahead of the traditional late September start of the U.S. television season.

In the 18-49 age group, Fox finished second, followed by CBS, and ABC, according to Nielsen data for the week starting September 24.

In total viewers, CBS was first with 10.7 million average viewers, followed by ABC (8.3 million), NBC 8.1 million, and Fox 6.9 million.

Fox is a unit of News Corp, CBS is owned by CBS, and ABC is a unit of Walt Disney Co..

(Reporting By Jill Serjeant; editing by Andrew Hay)

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