NBC’s Monday night lineup started the season strong, but it has declined in the two weeks since then. Last night the network slipped into third place, down 24 percent from its opening night.

The network averaged a 3.5 rating and 9 share, according to Nielsen overnights, down from a 4.6/11 overnight average on premiere week, when it placed a close second to ABC. Last week it averaged a 4.0/10, tying for second.

By comparison, ABC was down 13 percent from an opening-week 4.7/12, while CBS is down 7 percent from a 4.2/10.

NBC’s three dramas have seen double-digit declines since then as well. “Chuck” is down 28 percent from its premiere, from a 3.6 to a 2.6 last night, while “Heroes” slipped to a season-low 5.0, though it was still the night’s top-rated show, just ahead of ABC’s “Dancing with the Stars” at 4.9.

And “Journeyman,” “Heroes’” 10 p.m. lead-out, averaged a 3.0 last night, 19 percent below its season-opening 3.7 average.

Certainly some of the dropoff could be attributable to digital video recorder use, as Nielsen’s DVR sample has more than doubled since this time last year. Media people caution that seven-day-playback ratings will provide a much better picture of whether new series are actually losing viewers or viewers are simply time-shifting them after tuning in for the first episode.

But the declines may also signal lower viewership for the shows. Media buyers had pegged “Journeyman” as one of the season’s early casualties, saying it was too confusing. “Heroes” saw its 18-49 audience decline steadily at the end of last season, while comedy “Chuck,” though receiving excellent reviews, is competing with sitcom lineups on CBS and CW.

Meanwhile, ABC finished first for the night among 18-49s with a 4.1 average overnight rating and a 10 share. CBS was second at 3.9/10, NBC third at 3.5/9, Fox fourth at 2.5/6, Univision fifth at 1.6/4 and CW sixth at 1.1/3.
 
At 8 p.m. ABC led with a 4.7 for its first hour of “Dancing with the Stars,” followed by CBS with a 3.3 average for “How I Met Your Mother” (3.2) and “The Big Bang Theory” (3.4). Fox was third with a 3.0 for “Prison Break,” NBC fourth with a 2.6 for “Chuck,” Univision fifth with a 1.3 for “Amar sin Limites” and CW sixth with a 1.0 average for “Everybody Hates Chris” (1.1) and “Aliens in America” (0.8).

Both those shows did see growth in the CW’s target 18-34s from last week, with “Chris” up 20 percent to a 1.2 and “Aliens” rising 25 percent to a 1.0, though they were still last in the timeslot.
 
NBC took the lead at 9 p.m. with a 5.0 for “Heroes,” with ABC sliding to second with a 4.5 average for its last half hour of “Stars” and its first 30 minutes of “The Bachelor.” CBS was third with a 4.1 average for “Two and a Half Men” (4.4) and “Rules of Engagement” (3.8), Univision fourth with a 2.1 for “Destilando Amor,” Fox fifth with a 2.0 for “K-Ville” and CW sixth with a 1.3 average for “Girlfriends” (1.2) and “The Game” (1.4), which built on its lead-in for the second straight week.
 
At 10 p.m. CBS led with a 4.3 for “CSI: Miami,” with ABC second with a 3.1 for its last hour of “Bachelor.” NBC was third with a 3.0 for “Journeyman” and Univision fourth with a 1.5 for “Cristina.”
 
Among households, ABC led the night with a 9.8 average overnight rating and a 15 share. CBS was second at 7.4/11, NBC third at 5.1/8, Fox fourth at 3.9/6, Univision fifth at 2.0/3 and CW sixth at 1.6/2.