Robert Thornton was surprised to come in for the ride on Somersby in the Irish Independent Arkle Challenge Trophy at Cheltenham.

Tony McCoy was in the plate when the six-year-old won the Henry VIII Novices' Chase at Sandown in December, but the 14-times champion jockey will be on board Captain Cee Bee for his boss, JP McManus.

Thornton, who also rode Captain Cee Bee to Supreme Novices' Hurdle glory in 2008, was thrilled to get the call-up.

"Somersby was very good at Sandown and a pleasure to watch," Thornton explained.

"It's an honour to be riding him and one that is a little bit out of the blue.

"I wouldn't have ridden an awful lot for Henrietta (Knight) but I'm delighted to take the ride.

"I went down and sat on him the other day and loved him.

"I'll have a school on him in the next few days to get to know him properly and he looks like the one who could mix it with Captain Cee Bee.

"When I rode him in the Supreme, halfway down the back you'd have said I was the first beaten as I was off the bridle and struggling, but it was just pure class that got him through.

"He's definitely a top-class horse."

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