NBC was the top-rated network Thursday night with the top-rated show in the Nielsen overnight ratings for the key 18-49 demo.
CBS got off to a good start with NCAA Basketball coverage, winning each of the first three half-hours in prime. But after that, the ball dropped like New Year's Eve at Times Square, with CBS hoops falling to a distant third by night's end.
NBC won the night with a 4.7 rating/12 share average, powered by ER at 10, which averaged a 5.7/15, the night's highest-rated program.
ABC was second with a 4.3/11. It's top show was American Inventor, which won its 9-10 time period with a 5.1/13 for the second installment of the reality competition from American Idol's Simon Cowell.
CBS was a close third with its back-to-back NCAA Basketball regional semifinals, averaging a 4.3/11.
Fox was a distant fourth without Idol in the lineup, averaging a 2.4/6 for comedies That '70s Show and quirky newcomer The Loop, plus vet drama The O.C.