Revealing the Top 20 contestants to progress to the live shows, the singing contest commanded an audience of 10.09m (38.5%) from 7.30pm, peaking with 11.3m and rising 200k on Saturday's ratings.
Sandwiched between The Voice on BBC One, Countryfile (6.45pm) interested 5.88m (27.3%) and Silent Witness (9pm) logged 6.09m (24.2%).
Meanwhile on ITV1, the return of Vera took just 4.48m (17.2%) between 8pm and 10pm (+1: 345k/1.6%), prior to which All Star Family Fortunes entertained 3.74m (15.9%) at 7pm (+1: 345k/1.6%).
Over on BBC Two, new factual series Indian Ocean with Simon Reeve (1.95m/7.2%) and Ewan McGregor: Cold Chain Mission (1.75m/7%) performed respectably, before Match of the Day 2 scored 2.99m (17.1%) at 10pm.
Elsewhere, the latest Homeland recorded 1.91m (7.6%) on Channel 4 at 9pm (+1: 388k/2.1%), down from its season high last week.
Fellow US drama Once Upon a Time lost viewers, with the latest edition mustering 1.34m (5.3%) after Channel 5 moved the fairytale series back to 9pm to face Homeland.
Overall, BBC One pulled even further ahead in primetime with 29.4%, over double ITV1's 14.8% (+1: 1.1%). BBC Two followed in third with 8.2%, ahead of Channel 4's 5.2% (+1: 1%), and Channel 5's 4.4% (+1: 0.2%).
Of worthy note during the daytime, the London Marathon was seen by an average of 3.06m (30.8%) between 8.30am and 2pm on BBC One, while the Formula 1: Bahrain Grand Prix drew 3.65m (20.2%) on the same channel.
BARB ratings data supplied by Attentional