The teen drama's last ever episode averaged 1.4m and a demo score of 0.7 for The CW, according to Nielsen overnight data.
Meanwhile, American Idol's dominance continued with 16.7m (4.7) for Fox between 8pm and 10pm.
Betty White's Off Their Rockers made its presence known at 8pm with 7.2m (1.8), down 5m on its January pilot, but up on NBC's usual 8pm slot average.
Sitcom Best Friends Forever lost a third of White's lead-in, pulling in just 3.9m (1.2) at 8.30pm for its series premiere.
Then in the 9pm hour, Bent's final two episodes had 2.4m (0.9) and 2m (0.7), before Rock Centre with Brian Williams mustered 3m (0.7).
Happy Endings ended its second season with a disappointing 3.7m (1.6), inferior compared to last week's numbers. The rest of ABC's lineup were repeats.
For CBS, Survivor (10.1m/2.7) and Criminal Minds (11.2m/3.0) dropped, but CSI climbed to 11.9m (2.9) at 10pm.
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