The concluding hours of ”The Bachelorette,” airing on a special night, made ABC easily the top-rated network on Sunday, while CBS’ ”Big Brother” was down in its second week.

According to preliminary national estimates from Nielsen, ABC’s winning night opened with ”America’s Funniest Home Videos” (1.2/4 in 18-49, 5.3 million viewers overall), which matched last week’s summer-high level and led the 7 o’clock hour in 18-49. It was followed by the two-hour finale of ”The Bachelorette” (3.0/9 in 18-49, 8.6 million viewers overall) and the hourlong post-game special ”After the Final Rose” (3.2/9 in 18-49, 9.1 million viewers overall), which posted the franchise’s best scores of the summer. They were the top two programs of the night and were up vs. last year’s similar shows, which aired on its regular night of Monday.

Elsewhere, Fox’s ”Teen Choice Awards” (1.1/3 in 18-49, 3.0 million viewers overall) was flat year to year and was easily the night’s top show among teens (2.4/10). In the night’s opening hour, the net aired special repeats of ”The Simpsons” (0.9/3 in 18-49, 2.0 million viewers overall) and ”Family Guy” (1.2/4 in 18-49, 2.6 million viewers overall).

CBS opened with ”60 Minutes” (1.0/4 in 18-49, 7.3 million viewers overall), followed by ”Big Brother” (1.9/6 in 18-49, 5.4 million viewers overall), which was down 17% from its Sunday premiere of a week ago and ranked second in the 8 o’clock hour to the special ABC competition from ”The Bachelorette.” Two encores of ”The Mentalist” capped the night (0.9/2 in 18-49, 3.9 million viewers overall at 9 and 0.9/2 in 18-49, 4.2 million viewers overall at 10).

NBC had a quiet night with a two-hour ”Dateline” on the Colorado theater shooting (1.0/3 in 18-49, 4.2 million viewers overall), though it was up a bit week to week, followed by a two-hour repeat of ”America’s Got Talent” (0.8/2 in 18-49, 3.0 million viewers overall).

Preliminary 18-49 averages for the night: ABC, 2.6/8; CBS, 1.2/3; Fox and Univision, 1.0/3; NBC, 0.9/3.

In total viewers: ABC, 7.9 million; CBS, 5.2 million; NBC, 3.6 million; Fox and Univision, 2.7 million.