Music competish preems on the low side

Fox’s “Celebrity Duets” opened to mediocre numbers Tuesday night, placing a close second in young adults to the CBS combo of “Big Brother” and “Rock Star.”

Limited-run music contest, which pairs big-name artists like Smokey Robinson and Chaka Khan with some familiar faces like Cheech Marin and Lea Thompson, opened with a special two-hour preview before it shifts nights next week.

According to preliminary Nielsen data, “Duets” averaged a 3.0 rating/9 share and 8.1 million viewers overall from 8 to 10, also delivering a 9 share in both adults 18-34 and 25-54.

From 8 to 9, CBS’ “Big Brother: All-Stars” (prelim 3.1/10 in 18-49, 8.6 million viewers overall) beat “Duets” (2.9/9, 7.7 million) across the board. And in its second hour, the Fox skein (prelim 3.1/8 in 18-49, 8.6 million) ran second to CBS’ “Rock Star: Supernova” (3.2/9, 7.0 million) in 18-49 but won out in total viewers.

Simon Cowell skein will air in September for four weeks on Thursday and Friday, serving as a bridge between the net’s summer series and its coverage of postseason baseball.

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