The Manchester derby between United and City, the Premier League's biggest clash of the season, pulled in 2.56m (11.5%) for the channel's full coverage between 7pm and 11pm.
City's 1-0 win peaked with 4.4m (17.3%) at 9.50pm, having averaged 4.1m (16.4%) for the 90 minutes of soccer.
Sky Sports 1 pipped BBC One in the 9pm hour, and finished third overall in primetime.
Silent Witness slumped to 3.88m (15.2%) on the BBC's flagship channel, thumped by Scott & Bailey for a third week. ITV's rival crime drama logged 4.51m (17.7%) at the same time, adding 396k an hour later on ITV1 +1.
BBC Two's 1970s-themed season continued with 1.93m (7.6%) for The 70s at 9pm, and 1.47m (7.4%) for The Sound of the 70s at 10pm.
Meanwhile, Channel 5's ratings went from bad to worse, with The Gadget Show (759k/3.1%), Robson's Extreme Fishing Challenge (766k/3%) and 10 Things I Hate About 1987 (580k/3.2%) all losing viewers - possibly due to the football.
Across primetime, ITV1 came out on top with 21.2% (+1: 0.8%), ahead of BBC One's 19.1%. Sky Sports 1 was third with 11.5%, beating Channel 4's 5.9% (+1: 1%), BBC Two's 5.5%, and Channel 5's 2.8% (+1: 0.2%).
Elsewhere, cult reality show Made in Chelsea maintained 417k (2.3%) for E4 at 10pm, while Grimm (284k/1.1%) on Watch declined at 9pm - Game of Thrones climbed to 354k (1.4%) for Sky Atlantic at the same time.
BARB ratings data supplied by Attentional