CBS’s Monday lineup maintained its lead last night, even against stronger competition from Fox’s “24,” which held up nicely from Sunday’s season debut.

Buoyed by series-best performances from “The Big Bang Theory” and “How I Met Your Mother,” CBS averaged a 4.3 adults 18-49 rating and 11 share, according to Nielsen overnights, just ahead of Fox’s 4.1/10 for the night.

“Bang” led off with a series-high 4.4 rating, up 7 percent over its previous series high of 4.1 set in its most recent outing last month.

“Mother,” at 8:30 p.m., also hit a new series high of 4.8, bettering its old mark by 0.2. Both shows have been gaining momentum for the past two months, especially after ABC’s competing “Dancing with the Stars” went off the air in November.

“24,” airing another two-hour episode, nearly matched part one of its premiere Sunday night, slipping by just 0.1.

As a reminder, all ratings are based on live-plus-same-day DVR playback. Seven-day DVR data won’t be available for several weeks. Twenty-eight percent of Nielsen households have DVRs.
 
With CBS and Fox going one-two, ABC placed third for the night at 3.1/8, NBC fourth at 1.7/4, Univision fifth at 1.7/4 and CW sixth at 1.4/3.
 
CBS led each hour of the night, beginning with a 4.6 at 8 p.m. for “Bang” (4.4) and “Mother” (4.8), with Fox second with a 3.9 for the first hour of “24.” ABC was third with a 3.0 for “The Bachelor,” NBC and Univision tied for fourth at 1.9, NBC for “Superstars of Dance” and Univision for “Cuidado con el Angel,” and CW sixth with a 1.3 for “Gossip Girl.”
 
At 9 p.m. CBS was first with a 4.4 for “Two and a Half Men” (5.6) and “Worst Week” (3.3), followed again by Fox with a 4.3 for more “24.” ABC was third with a 3.5 for another hour of “The Bachelor,” Univision fourth with a 2.0 for “Fuego en la Sangre,” NBC fifth with a 1.9 for more “Dance” and CW sixth with a 1.5 for “One Tree Hill.”
 
CBS was first again at 10 p.m. with a 4.0 for “CSI: Miami,” while ABC moved to second with a 2.8 for “True Beauty.” NBC was third with a 1.7 for “Momma’s Boys” and Univision fourth with a 1.2 for “Cristina.”
 
Among households, CBS led the night with an 8.6 average overnight rating and a 13 share. Fox was second at 7.2/11, ABC third at 5.5/8, NBC fourth at 3.9/6, Univision fifth at 2.1/3 and CW sixth at 1.9/3.