Dancing With The Starz ABC TV RatingsMonday has become the most competitive night on television this season with NBC’s red-hot reality series The Voice, ABC’s veteran Dancing With The Stars and CBS’ formidable comedy block duking it out from 8-10 PM. In the first three-way faceoff last night, no one was left unscathed.

ABC’s Dancing With The Stars opened its season with a 3.5/9 among adults 18-49 and 18.5 million total viewers. It was down 34% in 18-49 from last spring’s premiere and down 13% from the fall debut when Dancing also faced a singing reality series on NBC from 8-10 PM, The Sing Off. This was Dancing‘s lowest-rated season premiere ever.

NBC’s The Voice (4.5/12) also was dinged up, down 13% to a season low from last week when it also faced repeats of CBS’ comedies — vs. originals last night. CBS’ comedies appeared affected more by the daylight savings time switch than by the increased competition from Dancing. The 8-9 PM series, How I Met Your Mother (3.4/10) and 2 Broke Girls (3.4/9), were down 6% and 11%, respectively, from their last originals three weeks ago. Meanwhile, the 9-10 PM duo of Two And A Half Men (3.8/9) and Mike & Molly (3.2/8) were actually up, by 6% and 10% respectively. NBC (3.8/10 in 18-49, 10.1 million) won the night in 18-49, with ABC (3.1/8, 16.3 million) and CBS (3.1/8, 9.5 million) tied for second.

With three networks posting solid ratings from 8-10 PM, Fox was squeezed out. House (2.0/6) was down 17% from its last original two weeks ago, with the daytime saving time also probably contributing to the decline. Alcatraz (1.5/4) was down 6% to a series low.

It was a close race at 10 PM, won by CBS’ Hawaii Five-0 (2.5/6), which was flat with its last original three weeks ago. With Dancing as a lead-in, ABC’s Castle (2.4/6) was up 14% from its last original three weeks ago when it followed The Bachelor. However, Castle‘s fast national included a minute of Dancing overrun and will likely be adjusted down, so it may tie NBC’s Smash (2.3/6), which was down 4% from last week. The CW aired reruns.