Chris Evans has proclaimed himself “defender of the faith” of quality broadcasting in the face of falling standards in the commercial sector. Three months before he takes over Terry Wogan’s breakfast show, the most coveted slot on BBC Radio, the former Virgin Radio owner revealed himself as a born-again advocate of the BBC.

His comments will strike many former colleagues in the embattled commercial sector as ungrateful and provocative. With advertising revenues coming under severe pressure, there is a widespread belief in commercial radio that Radio 2 is reneging on its public service remit by targeting too young an audience and stealing listeners from the likes of Heart FM. Hiring a broadcaster such as Evans to replace the more genteel Wogan has only intensified this criticism.

Evans, 43, has spent much of his lucrative but frequently self-destructive career in the commercial sector. But after being welcomed into one of the BBC’s top broadcasting jobs, he has apparently acquired the fervour of the new believer. “I feel like a defender of the faith,” he told The Times Cheltenham Literature Festival at the weekend.

“When you work for the BBC and you take your job seriously ... when you are surrounded by all these people doing great things and you get this massive reaction from listeners and you see the stuff that’s going on around — a lot of it is about making money and spiralling standards. You think ‘Jeez, we’ve got to do a good job here, for loads of reasons’.

“The number one reason is the audience, always. The number two reason for me is to ensure the longevity of the BBC. Without being a purist, I don’t want it to disappear because it’s the one thing that’s propping the industry up.

“If we’d have gone the way of commercial broadcasters — which they had to do, it’s sort of not their fault in a way — we’d have all been going down, and what would you be listening to and what would you be watching? Goodness me ... ”

Evans started in commercial radio, then moved to the BBC station GLR in London before fronting The Big Breakfast on Channel 4 in 1992. Radio 1 headhunted him in 1995 for the breakfast show. He left in 1997 after unreliable behaviour culminated in him asking for Fridays off.

Richard Branson signed him up for Virgin Radio in 2000 and later that year Evans bought the station, selling it with the rest of his company, Ginger Media Group, to Scottish Media Group for £225 million. In 2001 the station’s new owners sacked Evans and four years later he was brought back into the BBC fold. He has publicly thanked the BBC for giving him a “second chance”.

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