TV Ratings: Special 'CSI' Holds Steady, 'American Idol' and 'Nashville' Go Low

In the third backdoor pilot of the season, Patricia Arquette heads to the CBS procedural and narrowly loses the hour to "Chicago P.D."
Patricia Arquette in "CSI"

CSI tested the waters with what could be its third spinoff on Wednesday night. CBS' procedural mothership welcomed Patricia Arquette in the backdoor pilot, and the series pulled a steady 1.8 rating among adults 18-49 (up a tenth) and 9.95 million viewers.

The episode had a lead-in from Survivor (2.3 adults) and Criminal Minds (2.2 adults), both off a tenth of a point from last week, giving CBS a dominant 2.1 demo rating and 9.9 million viewers for the night.  

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Fox ranked second, with American Idol pulling a 1.8 rating among adults 18-49 and 8.6 million viewers. Off three-tenths of a point in the demo, it marks a series low for performance shows.

ABC saw much of its block take big hits. After a steady The Middle (1.8 adults), Suburgatory (1.4 adults) and Modern Family (2.8 adults) dropped a respective three- and seven-tenths of a point. Mixology (1.3 adults) fell two-tenths, and Nashville hit a series low with a 1.2 rating in the demo. ABC averaged a 1.6 adults rating and 5.5 million viewers. 

NBA playoff preemptions make NBC's nightly scores tentative, but Revolution (1.4 adults) was steady at the top of the night. Law & Order: SVU (1.8 adults) shed three-tenths of a point, while Chicago PD (1.9 adults) improved three-tenths. The network took a 1.7 adults rating and 6 million viewers.

Over on The CW, Arrow (0.8 adults) was improved by a tenth of a point and The 100 (0.6 adults) matched last week's score.