A repeat of CBS comedy “The Big Bang Theory” towered in the ratings over everything else on a quiet Thursday night, which also saw solid numbers for encores of a “Saturday Night Live” special on NBC and “Shark Tank” on ABC.

According to preliminary national estimates from Nielsen, “The Big Bang Theory” kicked off the night for CBS with a 2.6 rating/9 share in adults 18-49 and 11 million viewers overall, topping the combined 18-49 delivery in the timeslot for ABC, NBC, Fox and CW. It was followed by a mini-marathon of “The Millers” repeats, starting with its regular time period (1.7/5 in 18-49, 7.4 million viewers overall) and episodes at both 9 (1.1/3 in 18-49, 5.3 million viewers overall) and 9:30 (0.9/3 in 18-49, 4.4 million viewers overall). A repeat of “Elementary” closed out the night (0.9/3 in 18-49, 5.3 million viewers overall).

CBS won the night in 18-49, 25-54 and total viewers.

ABC opened with a special repeat of Friday program “Shark Tank” (1.3/4 in 18-49, 5.6 million viewers overall), which delivered the best result for a series in the timeslot for the net since the series premiere of “Once Upon a Time in Wonderland” in October. Not faring as well was the two-hour “20/20” special “Mysteries of the Castle: Beyond Downton Abbey” (1.0/3 in 18-49, 4.8 million viewers overall), which saw both its young-adult and overall viewership dwindle with each half-hour.

NBC started slowly with repeats of “Parks and Recreation” (averaging a 0.6/2 in 18-49 and about 2.1 million viewers overall) but then got a lift from a repeat of “The Women of SNL” (1.3/4 in 18-49, 4.0 million viewers overall), which was the broadcast leader in 18-49 from 9 to 11.

Fox aired repeats of “Glee” at both 8 (0.4/1 in 18-49, 1.6 million viewers overall) and 9 (0.3/1 in 18-49, 1.4 million viewers overall). And CW went with encores of “The Vampire Diaries” (0.3/1 in 18-49, 0.9 million viewers overall) and “Reign” (0.3/1 in 18-49, 0.9 million viewers overall).

Preliminary 18-49 averages for the night: CBS, 1.4/4; ABC and NBC, 1.1/4; Univision, 1.0/3; Telemundo, 0.6/2; Fox, 0.4/1; CW, 0.3/1.

In total viewers: CBS, 6.5 million; ABC, 5.1 million; NBC, 3.4 million; Univision, 2.9 million; Fox, 1.5 million; Telemundo, 1.4 million; CW, 0.9 million.