Updated

Some humbling news for the pros: By a wide margin, TV viewers prefer the amateurs.

Nearly twice as many people watched "American Idol" than the Grammy Awards Wednesday when the two music programs went head-to-head in prime time, according to preliminary estimates by Nielsen Media Research.

The "Idol" audience on Fox was 28.3 million while the Grammy Awards were being watched by 15.1 million people from 8 to 9 p.m. EST, Nielsen said.

Within that hour, featured performers on "music's biggest night" included Madonna, John Legend, Coldplay and U2. The Irish rockers were the big Grammy winners, earning album of the year and song of the year for "Sometimes You Can't Make It on Your Own."

After "Idol" went off the air, the Grammys picked up a little steam. Overall, from 8 to 11 p.m., the show averaged 17.6 million viewers. The final viewership figure for the show, which lasted until 11:30 p.m., was not immediately available, but was likely to be slightly lower than 17.6 million.

The least-watched Grammy telecast since Nielsen began keeping records was the 17.2 million who watched in 1995. Last year's show was seen by 18.8 million people, with 26.3 million viewers in 2004.

Former "American Idol" winner Kelly Clarkson won two Grammys, but didn't mention the Fox show in her tearful acceptance speeches.

The music pros can take a little comfort in at least slowing the "American Idol" momentum. It was the first time in seven telecasts this season that "Idol" was seen by fewer than 30 million people.