When I Get Older, which saw celebrities move in with troubled pensioners, launched with only 3.46m (15.5%) at 9pm.
Despite a big lead-in audience from EastEnders, the documentary series lost out to a repeat of ITV1's Midsomer Murders, which drew 3.99m (18.3%) between 8pm and 10pm and 230k (1.1%) on +1.
Andy Murray's short visit to BBC One in the 7pm hour scored an average of 5.29m (25.5%) for his quarter-final victory, while The One Show aired on BBC Two to 2.09m (10.4%).
BBC Two also aired Today at Wimbledon (1.58m/7.4%) and The Secret History of Our Streets (1.52m/6.8%).
24 Hours in A&E, which was severely dented by the football last week, rallied to 2.38m (10.7%) for Channel 4 at 9pm (+1: 542k/3%), prior to which River Cottage interested 1.49m (7%) at 8pm (+1: 243k/1.1%).
Meanwhile, NCIS took 1.65m (7.2%) for Channel 5 at 9pm (+1: 134k/0.7%), then 1.41m (7.7%) watched the latest Big Brother highlights show.
Overall, BBC One narrowly led primetime with 20.8% against ITV1's 19.4% (+1: 0.9%). BBC Two earned third place with 6.4%, just ahead of Channel 4 which had 6% (+1: 1.2%), while Channel 5 claimed 5.3% (+1: 0.3%).
BBC Three's lifestyle offering Cherry Healey: How to Get a Life logged 570k (2.5%), making it the fifth most-watched multichannel programme of the evening.
BARB ratings data supplied by Attentional