'Saturday Kitchen' has lost one million viewers since James Martin left the show.
The BBC One cooking programme, which is currently being taken over by guest presenters, has been dubbed a flop as viewers have refused to tune in since the well-loved chef, who fronted the show for a decade, quit in February.
An insider told The Sun newspaper: "Viewers loved James and the show is really struggling without him.
"People don't like change and without a regular presenter, fans are beginning to lose interest. The guest chefs aren't working as well as bosses had hoped."
And while stand-in presenter Donal Skehan was a hit with viewers when he made his debut on Saturday (11.06.16), the BBC have a lot of work to do if they want to keep fans.
The source added: "It's not looking good as the ratings are only going down. However, Donal's debut on Saturday seemed to go down well. But the BBC are going to need to do more to win fans back."
James - who presented 'Saturday Kitchen' from 2006 to 2016 - previously compared his departure to that of when One Direction announced they were "splitting."
Speaking about the response he got after he announced his exit, he said: "It was surreal. I didn't think it was a big deal, but it was everywhere - the equivalent of One Direction splitting."
In the four months since he left, there have been several guest presenters including The Hairy Bikers, Lorraine Pascale and Michel Roux Jr.
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