ABC's controversial new reality series "The Glass House," which sparked a lawsuit from CBS due to its seeming similarities to "Big Brother," fell a considerable 20 percent in ratings Monday night from its lackluster premiere.
Meanwhile, NBC and Fox shared first place, with "America's Got Talent" scoring the night's best individual ratings, according to preliminary numbers.
NBC tied Fox in ratings with an average 2.3 rating/7 share in the advertiser-coveted 18-49 demographic and took first place in total viewership outright with an average 7.8 million.
"The U.S. Olympic Trials '12: Swimming Finals" at 8 p.m. posted a 1.9/6 in the demo with 6.9 million total viewers, while "America's Got Talent" the following hour showed a modest ratings increase with a 3.0/8, and drew 10.4 million total viewers (which also made it the night's most-watched program).
"American Ninja Warrior" at 10 drew even with last week for a 2.0/5 and attracted 6 million total viewers.
Fox, which came in third in total viewers with 5.4 million, aired "Hell's Kitchen" at 8, which was down 8 percent in the demo with a 2.3/7 and drew 5.5 million total viewers, and "MasterChef at 9, which was also down slightly in ratings with a 2.2/6 and 5.6 million total viewers.
ABC took third place in ratings with a 1.9/6 and second in total viewers with 5.7 million. "The Bachelorette" at 8 dipped slightly from last week with a 2.2/7 and took 7 million total viewers, while "Glass House" at 10, which last week premiered with a 33 percent drop from last summer's equivalent premiere of "Extreme Makeover: Weight Loss Edition," fell to a 1.2/3 with 3.3 million total viewers.
Univision came in fourth in ratings and fifth in total viewers with a 1.4/4 and 3.6 million.
CBS, which drew fifth place in ratings and fourth in total viewers with an average 1.2/4 and 5.2 million, ran repeats throughout the night.