SINGER Michelle McManus saw radio host Suzie McGuire being grabbed by her husband and branded a slut after posing for pictures with young soldiers at a military ball fundraiser, a court has heard.

The TV host also claimed that shortly after she saw the Clyde One presenter clash with Derek Mitchell, 35, she saw him digging his fingers into his wife's hands to stop her from speaking.

And the former host of The Hour, STV's lifestyle magazine show, said the events left her feeling so uneasy that she could not stay in their company.

Mitchell was on trial yesterday accused of assaulting Ms McGuire repeatedly, damaging her car and following her over a five-year period.

McManus, who shot to fame after winning the second series of TV show Pop Idol, was the first witness to give evidence in the case.

The 34-year-old singer spoke about the alleged bust-up, which she said took place at five-star Mar Hall, in Bishopton, in September 2011.

She told Paisley Sheriff Court she had been booked to sing at the event, which was being organised to raise funds for Erskine Hospital, which helps care for army veterans, while Ms McGuire was supposed to be hosting.

But she said she had to take over Ms McGuire's hosting role when the drive-time presenter failed to turn up on time and that, when she eventually did turn up, she saw the incident take place.

She told the nine men and six women of the jury: "Suzie came in with Derek after the meal. Suzie was full of apologies.

"I think she was a bit embarrassed at being late - she was booked to host the start of the event and wasn't there for it."

Ms McManus said there were several young soldiers in full uniform who asked her and Ms McGuire to pose for pictures.

She said: "We were having fun, trying on hats and getting pictures taken with them. At that point I stepped aside to make a phone call or send a text.

"Derek came to the side and he looked angry. He grabbed Suzie by the arm and said, 'You're really embarrassing me. You're behaving like a slut, but then again you are a slut', which I was quite taken aback by. There was nothing, absolutely no reaction whatsoever, which was the most baffling thing for me.

"In my opinion it was almost as if it was the norm."

Ms McManus, who described herself as being a work colleague of Ms McGuire's for the last decade, said the couple then returned to their table.

She said that just a few minutes later she again witnessed an incident between the pair.

She said: "It looked like Derek was holding Suzie's hand. Suzie was telling a story, she was holding court at the table and everyone was laughing and joking at it.

"It was like he was digging his nails into the top of her hand.

"Whatever he did to her hand stopped her from talking. His nails were in the grooves between her fingers. Suzie did stop the story and just kind of removed her hand away."

Ms McManus said she left the couple and the others and went up to her room.

She said she next saw Derek at another event around a year later and spoke briefly to him.

She told Amanda Gallagher, prosecuting: "I said, 'Your wife looks amazing tonight'. He said, 'Yeah, she does, but I need to keep her in check - you know what she's like.' He was fine, very chatty and very lively."

Accountant Mitchell denies a host of assaults on his wife. He has entered a special defence of self defence in relation to one charge. The trial, before Sheriff Susan Sinclair, continues at Paisley Sheriff Court.