Craig Revel Horwood has confessed he accidentally held up the wrong score while judging Strictly Come Dancing - then had to find fault with the contestant to avoid admitting his blunder.

The notoriously hard-to-please panellist says he aimed to give a seven - a generous score for him - but ended up giving a four to one poor dancer.

Craig admitted the gaffe during an edition of BBC2's Sarah Millican Television Programme to be screened tomorrow.

"Of course, because it was a low score I then had to find as many things wrong with it as I could," he said.

The choreographer - whose tenth recent series of Strictly finished last month - did not name the hapless contestant. "I remember it was a four but I wanted to give a seven, you see, so it was a bit of a disaster." He added: "It's live television - what can you do, darling?"

Sarah also dresses as a naughty nurse as she teams up with guests from BBC1 series Casualty for a comedy sketch.

She is joined by Tony Marshall, Suzanne Packer, Charles Dale and Azuka Oforka from the show as she uses a defibrillator on a patient who is wheeled on to the show.

Sarah nipped off to get changed into a PVC outfit for the scene after stepping behind a curtain. She tells them: "I've got my own uniform - it's wipe-clean."

Suzanne - who plays Casualty's Tess Bateman - told how viewers asked her for medical advice in real life. "It normally happens to me on a Saturday morning when I have popped out to the DVD store in my pyjamas and someone asks me about their bleeding piles," she said.

:: The Sarah Millican Television Programme is screened on BBC2 on Tuesday at 10pm.