Executives from Channel Ten will be nervously awaiting overnight viewing figures to learn if the launch of the fourth series of its blockbuster MasterChef lives up to expectations.

At about 8.40am today, news from the ratings agency OZTAM will confirm whether it will be champagne or commiserations for the No. 3 commercial TV network.

Ten's head of programming David Mott and chief executive James Warburton will be disappointed if last night's opening falls under 1.5 million viewers. Opening nights for the previous MasterChef have consistently garnered that figure. Typically, ratings soften and then gradually build up to a climax.

There is a widespread expectation among media analysts that this season will fail to match last year's figures, which were down 15 per cent on the previous season.

Much is riding on Masterchef for Channel Ten, which has started the year poorly in ratings.