Urging viewers to watch her tonight instead of 71-year-old Tom in his spinning judge's chair on the BBC1 show, she joked: "He might be spinning in his grave next week."
Boss Simon Cowell looked shocked by her gag at the launch of the ITV1 show's sixth series. It followed her own near-death experience when she gave birth to new daughter Hollie.
But show insiders last night insisted Amanda meant no offence to the Delilah singer, adding: "She has the utmost respect for Tom."
A fierce spat erupted between the rival show's stars before they clash in a ratings war tonight.
Amanda, 41, joins boss Cowell and fellow judges Alesha Dixon and David Walliams on the ITV1 show.
Last night Cowell — who had been criticised by Sir Tom over his right to judge singers — hit back at the Welsh crooner's ability to pick wannabe stars.


He said: "Most artists who try and run record labels fail. That's why they are artists. Can a singer judge another singer as well as a record executive?"
The music tycoon also blasted "petty" Beeb bosses over the scheduling clash, laying the blame firmly at their door.
He said: "They're the ones who seem to be making it into a battle. We were always going to air in March because of my timings.
"The BBC are doing this as the more they talk about us the more headlines they get. But I don't like it when the shows clashes. It is petty scheduling."
But BBC1 controller Danny Cohen played down the battle for viewers, saying: "I'm not going to put a number on what we see as success for The Voice."


Yesterday Cowell said this year's BGT will be the best ever, erasing memories of last year's uninspiring run.
He said: "There's a mixture of good and what I call good old-fashioned British eccentricity.
"The best way to judge the show is not to take it too seriously, but the good ones are always going to get through and that is the important thing."
With a glint in his eye, he added: "There will be some strippers of course — one or two."

And he said there will be nine acts in the semi-final instead of eight, ensuring even more talent gets through.
Simon, 52, also sang the praises of Walliams, 40 — who rose to fame alongside Matt Lucas in BBC1 comedy Little Britain. Cowell said: "I've been trying to get David to do this show for the past two years. There were these two bellringers last year and I texted him saying: 'It's you and Matt!'
"Some of his characters on Little Britain are like some of our contestants. I thought he'd really fit into that kind of British eccentric humour. He's been a revelation."

Big Jon's a belter

BOOKIES have already predicted that BGT will win the Saturday night ratings war — with William Hill putting the ITV1 show at 2/9 on and BBC's The Voice trailing on 3/1.

A spokesman for the firm said: "The return of Simon to the BGT panel will probably be enough on its own to secure an opening week victory over the Beeb."

TV recorders will be needed by those who want to see both — the shows overlap by 20 minutes.

SHOWBIZ veteran Sir Tom Jones told The Sun yesterday how he was staking his reputation on the success of The Voice.

And he said he even fears taking abuse in the street if he gets it wrong.

The 71-year-old crooner explained: "You are throwing yourself out there and making decisions. People at home could be thinking, 'What the f***? Why would he do that? What's the matter — is he deaf?'

"When you are out and about on the Tube, or in a cab, the drivers are going to go, 'Hey Tom, the show is s***'. We have to make the show as good as we possibly can and whatever is thrown against you, fight back."

BBC1's The Voice, which starts at 7pm, clashes with Britain's Got Talent, beginning at 8pm on ITV, for a vital 20 minutes — but Sir Tom said: "The ratings war is out of our hands.

"As long as we get a fair crack of the whip, then it is up to the viewers. At the end of the day it is always up to the viewers."

He added: "With some other shows, like BGT, all kinds of talent comes on. But The Voice is purely about what people sound like — that's the unique thing."

Sir Tom — on the show with fellow mentors Will.i.am, Jessie J and Danny O'Donoghue — had warmed up for tonight's ratings fight by taking a stinging swipe at Simon Cowell.

The Welsh legend insisted ITV show guru Cowell was NOT a good judge of singers because he has NEVER had a go himself.

Sir Tom said: "I have problems when people who have never got up on a stage to sing judge those who do. Who are they to say?

"Simon Cowell is a record man, not a singer. How can someone give advice if he or she is not qualified?

"The shows with judges from other areas of show business are all very well and good.

"But The Voice is unique because the four coaches are all singers, can all make records and know what they're talking about."

The Sex Bomb and It's Not Unusual star believes he already has five potential winners lined up. But he told The Sun he hated having to dash hopefuls' dreams.

Tom added: "That's the hardest part — sending people home. I don't like that at all. I have never had to do that before in my life.

"When I have watched other talent shows and seen people getting all emotional, I thought that it was just showbusiness.

"But when you are there, you realise how difficult it is. You have their future in your hands. It's not easy. In fact I'm going to be in trouble when I get home. There was a Welsh girl singing a Linda Perry song, very similarly to the original. I didn't pick her.

"But I did say to her she hasn't lost forever — she is young enough to come back next year."

MENTOR Danny O'Donoghue says he is having coaching — to stop himself swearing on The Voice live shows.

The foul-mouthed rocker said: "I tend to curse a lot so forgive me when I get to the live shows.

"I'm in training now for the next seven weeks to not curse on the live shows. I'm very passionate and I have a limited dictionary to express myself with." The Script frontman said he had been impressed by the "nerves of steel" singers on the show so far.

He confessed he would not have had the courage to audition for a TV talent show.

Irish star Danny, 32, added: "I think in the day we are living every phone is a camera, so kids are a lot less shy."