The X Factor audience slips by nearly 1m viewers on last year's opener to get 6.8m viewers

The overnight ratings figure, which includes the main ITV Channel, ITV HD and ITV+1, gave it a 34% share of the audience between 8pm and 9.30pm last night. But this was down on last year’s launch episode overnight figure of 7.64m, a share of 39%.

This is understood to be the lowest overnight ratings performance for an opening edition of the show since 2005 when it averaged 6.7 million according to the overnights.

But at least Simon Cowell and co can comfort themselves with the fact that the entertainment juggernaut beat Casualty’s audience of 5.1 million on BBC1.

Also, The X Factor's audience is certain to increase when the numbers are consolidated. Last year’s X Factor debut added two million viewers when the seven day catch-up was consolidated and ITV will be hoping for a similar performance again. The X Factor's audience peak was 7.5m viewers last night.

On BBC1, the dramatic 100-minute Casualty special episode averaged 5.1 million viewers between 8pm and 9.40pm according to the overnight figures.

This was a 26% share of the total available audience for an eventful episode which saw a lethal helicopter crash and the return of some old favourites from the hospital drama.

The Xtra Factor live on ITV2 was watched by 809,000 viewers between 9.30pm and 10.30pm last night, with a peak figure of 942,00. It was the second most watched digital channel programme of the day, just behind Hull v Manchester United on BT Sport which averaged 827,000 viewers.