It has some time to recoup, but NBC's ambitious gameshow "The MIllion Second Quiz" opened to soft numbers Monday night.

The around-the-clock quiz show hosted by Ryan Seacrest settled for a 1.7 rating/5 share in adults 18-49 and 6.5 million viewers overall in the 8 o'clock hour, according to Nielsen. While "MSQ" beat tennis on CBS and repeats on ABC and Fox, it merely matched NBC's demo delivery in the hour a week earlier with reality show "American Ninja Warrior."

And in a not-so-good sign, "Quiz" dropped from a 1.7 in the 8 p.m. half-hour to a 1.6 in the 8:30 p.m. half-hour. In total viewers, it started with 6.8 million but finished with 6.2 million.

The show follows a group of contestants who compete for up to $10 million in a quiz competition spanning 1,000,000 seconds (or about 11 days). With the exception of next Sunday when it airs "Sunday Night Football," NBC is devoting the 8 o'clock hour in primetime to the series very night through next Thursday.

Elsewhere on the broadcast networks Monday, CBS' "Under the Dome" fell to a season low one week from its finale, averaging roughly a 2.2 rating/6 share in adults 18-49 and 9.3 million viewers overall. The preliminary numbers are murky because CBS opted to start TV's top-rated new show of the summer about 30 minutes late in the Eastern and Central time zones; the net aired U.S. Open tennis until about 8:55 p.m. ET and then aired some comedy repeats before starting "Dome" at about 10:30.

Prelims for ABC are inflated due to a preemption in Philadelphia for Eagles football, but the season finale of "Mistresses" earned a 1.4/4 in 18-49 and 5 million viewers overall. In the nationals, it figures to come in below its penultimate episode of last week, which also was a 1.4/4.

ESPN dominated the night with its "Monday Night Football" doubleheader. The first game, between Washington and Philadelphia, did a big 11.6 overnight rating, which should translate to around 17 million viewers.

Preliminary 18-49 averages for the night:


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