A weather delay that pushed the game past midnight ET contributes to the year-to-year decline.

The NFL's opening game of the 2018 season brought in smaller ratings than the 2017 kickoff in the preliminary numbers.

NBC's broadcast drew a 13.4 household rating in metered markets, down about 8 percent from 14.6 for last year's opener. A weather delay that pushed kickoff back 45 minutes to 9:05 p.m. ET likely contributed some to the decline, as the game between the Philadelphia Eagles and Atlanta Falcons ended after midnight ET.

Despite the declines, NBC dominated the ratings for the night. In metered markets, its 13.4 doubled the combined averages for ABC, CBS and Fox (6.7). NBC says the game's metered-market rating was the best for any sporting event since the Winter Olympics in February.

The NFL's TV ratings suffered a decline in 2017, falling about 9 percent for the regular season vs. 2016 (a smaller slide than the overall erosion on the broadcast networks).

In the fast nationals, NBC's NFL coverage averaged a shade under 19 million viewers from 9-11 p.m., pending updates, along with a 6.6 rating among adults 18-49. Those numbers will likely go up in the finals with adjustments for the live broadcast.

In "fast official" ratings, the game averaged 19 million viewers on NBC, down 13 percent vs. the final numbers for the 2017 kickoff (21.79 million). Including digital, the total audience for the game was 19.5 million, with an average minute audience of 570,000 via streaming. The latter figure is a 61-percent improvement vs. a year ago (355,000).

Elsewhere Thursday, Big Brother topped the night's non-football offerings with a 1.4 in the 18-49 demo on CBS, up a tick from a week ago. ABC's Match Game also rose a tenth of a point to 0.6, while Take Two (0.4) was in line with last week.

NBC averaged a 6.0 among adults 18-49 in primetime, pending updates. That's almost triple the combined totals for CBS (1.0), ABC (0.6), Fox (0.4) and The CW (0.2).

In late night, a delayed Tonight Show got a big NFL boost and scored a 1.0 in adults 18-49 in the metered markets. The Late Show came in at 0.4 and Jimmy Kimmel Live at 0.3 in their normal 11:35 p.m. slots. Late Night posted a 0.6 (excluding the show's final 15 minutes), while The Late Late Show and Nightline each averaged 0.2.

Friday, Sept. 7, 2:35 p.m. Updated with more accurate NFL audience figures.