The debut of the eighth season of "American Idol" averaged 30.1 million
viewers Tuesday night, down 10% from the previous year's debut of 33.4 million, according to early ratings from Nielsen Media Research.

That being said, "AI" still demolished the competition, with CBS's slate of "NCIS" and "The Mentalist" during the same two-hour time frame landing in second place and tallying 18.5 million and 18 million viewers, respectively.

By the half hour, "AI" had 18 million viewers in the 8-8:30 half hour; 30 million in the 8:30-9 slot; 32.7 million in the 9-9:30 slot - which dropped slightly to 32.5 million in the 9:30-10 slot.

Mediaweek's Marc Berman contributed to this report.