Starring Hugh Bonneville as the London Games' hapless boss Ian Fletcher, the mockumentary made its terrestrial debut with 974k (5.2%), having aired on BBC Four last March.
The British Comedy Award-winning show, despite achieving its best audience to date, was quite a way short of what BBC Two normally averages in the half-hour between 10pm and 10.30pm.
However, a lead-in of just 623k (2.9%) from 9pm's Reverse Missionaries did not help. In contrast, Mastermind (1.96m/9%) and Gardeners' World continued to flourish in the 8pm hour.
Elsewhere on Friday night, Benidorm's ratings rebounded to 5.58m (25.6%) at 9pm, adding 310k (1.8%) on ITV1 +1, its slightly lacklustre performance last week having been a result of facing Sport Relief.
BBC One was second in the hour with 3.94m (18.1%), as the channel reverted to its New Tricks repeats formula, prior to which Len Goodman's Titanic documentary set sail with 2.98m (13.1%) against Coronation Street.
Meanwhile, ITV's Poms in Paradise performed slightly worse against EastEnders with 2.78m (12.1%) at 8pm (+1: 166k/0.8%).
The Million Pound Drop Live anchored Channel 4's schedule with 1.57m (7.6%) from 9pm (+1: 167k/1.1%). Rude Tube followed with a commendable 1.04m (8.1%) at 10.30pm (+1: 167k/1.1%).
Eddie Stobart: Trucks and Trailers secured 1.28m (5.7%) for Channel 5 at 8pm, then 1.42m (6.5%) watched The Mentalist.
Overall, ITV1 clawed back its primetime lead with 24.4% (+1: 0.8%) against BBC One's 19.9%. BBC Two claimed third place with 6%, ahead of Channel 4's 5.5% (+1: 0.7%) and Channel 5's 4.8% (+1: 0.2%).
BARB ratings data supplied by Attentional