When customers joked to supermarket checkout girl Ann Garner that they had seen her in the new advert for her employer, she wondered what they were talking about.

It was only when her colleagues pointed out that she bears more than a passing resemblance to rock legend Ozzy Osbourne's wife Sharon that she decided to embrace her new-found fame.

The 46-year-old mother from Sutton Coldfield hatched a plan with her co-workers and decided to dress up like Sharon, ITV's X Factor judge who last week became the face of the supermarket chain Asda.

On Saturday, without telling bosses what they were plotting, Ann and her colleagues put on wigs and black outfits and got on their tills, much to the amusement of customers who found themselves faced with nine Sharon Osbourne lookalikes.

Ann said: "I couldn't believe it when people started telling me I looked like Sharon Osbourne.

"I was a bit upset at first, but after seeing her on TV I realised how good she looks for her age and I thought it would be funny if a group of us dressed up like her. After watching the advert we all went out and bought wigs - I didn't need one because my hair already looks like Sharon's - but everyone else looked great in theirs.

"We decided that on Saturday morning we'd all go into work and instead of wearing our green uniforms we wore black outfits in the way you always see her.

"I thought the managers might be funny about it but they all laughed when we came in."

Customers at the Minworth store, just a few miles from where Ozzy grew up in Aston, enjoyed the practical joke.

One shopper, Caroline Fellows, said: "I couldn't believe my eyes when I saw them all sitting at their tills.

"It certainly made the trip to pick up my week's shopping a more interesting experience than it normally is."

An Asda spokesman said: "Normally Asda staff have to wear uniforms but we thought we'd make an exception because Ann looks so much like Sharon.

"We thought it would be a laugh and it's nice to see our staff getting behind our campaigns."