Jackson's sister says there is an extra demand on the ex-athlete

Jackson will square up to DJ Zoe Ball and cricketer Darren Gough for the live final of the Saturday night TV show.

Jackson's sister Casualty actress Suzanne Packer said of his success so far: "It's been nearly 12 weeks and I'm still stunned."

Ladbrokes put Jackson at 8-11 with Zoe Ball at 5-2 and Darren Gough at 3-1.

Ms Packer - who plays dedicated nurse manager Tess Bateman in Casualty - will be among the audience for the live dance floor denouement between the celebrities.

Remarking on her brother's new-found talent, she told BBC Radio Wales: "It's a shock. I've always known that he's got good rhythm, but I would never have dreamt that he could retain dance sequences and then perform them as though he was a professional.

Casualty actress Suzanne Packer says she admires all contestants

"I will certainly be rooting with my whole being for Colin to win."

She added: "I have to say, if it went on performance, strictly, then Colin should win. It's not that Darren hasn't been progressing brilliantly, but if I was to go and be incredibly objective, if I was talking about ability and skill factor, I definitely think Colin is ahead there."

The actress praised all the contestants for being willing to "come out of their comfort zone" by taking on the live television challenge. But, she said, her brother had to overcome another challenge - simply being a man.

"The man has to not only learn the steps and the routine but also has to learn to lead, so if you're an absolute beginner, you really will struggle to take the floor," she said.

'Extra demand'

"Whereas, a woman can be made to look good if they have a very good male partner who's leading.

"I know this from very personal experience. I'm not a dancer but I've done musicals where I've had to dance and I've been fortunate to have male partners who are dancers.

"And I've come out, and people have said to me 'I never knew you danced so well'. They (male partners) made me look good, whereas I think there's just an extra demand on Colin."

Described as Britain's finest ever sprint hurdler, Jackson has already done better in the dance competition than fellow Welshman Aled Jones, who made it to the semi-finals last year.

His Saturday night performances have also landed him a spot performing Singin' in the Rain during the BBC Sport Personality of the Year show last Sunday.