Sam Clipperton is a little overwhelmed by the circumstances of his call up for Mr Stunning in Sunday’s Chairman’s Sprint Prize but says he is approaching the race with a calm confidence.

Clipperton was already booked for the John Size-trained Western Express in the Champions Mile and eagerly looking forward to a chance at his first Hong Kong Group One in that race, before the events of Wednesday saw Nash Rawiller disqualified and Size looking for a rider for the Hong Kong Sprint winner.

“They are hardly the normal circumstances that you get a ride and really an extraordinary situation, but if it wasn’t me, it would be someone else riding Mr Stunning. I put my hand up, hoping, and I’m thrilled with the opportunity,” Clipperton said.

“I’ve never ridden Mr Stunning but I’ve seen a bit of his rear end in races and he’s a horse that would give any jockey confidence. He looks a terrific, straightforward horse with all the capabilities to adapt and make his own luck. He’s got a great winning record and he’s proven in the top races. He’s the complete package.”

Top Australian jockey Nash Rawiller banned for betting offences by Hong Kong Jockey Club

When Size told Clipperton on Wednesday he could have the ride, he also asked the jockey to get to Thursday’s barrier draw and select the gate.

“That made me a little nervous. At least it’s a smallish field so it’s not like I might have pulled 14 but I was very happy with three,” he said. “Obviously it’s not an easy race, it’s a Group One, but I think he’s a great chance.”

Western Express he knows much better, having been aboard three times this season including the Hong Kong Mile when he finished second to Beauty Generation.

“He can be a bit slow at the start so I think he’s better in the smaller field – he won’t be as far away as he is in a field of 14,” he said. “He’s already shown he’s up to these horses in the big miles. And, when I trialled him the other day, he was very strong, he towed me to the line. When he trials like that, he is in really good form.”

Western Express has potential to open new horizons for Clipperton as he holds an entry for the Yasuda Kinen in June, a race Size likes to patronise, but the rider is not getting ahead of Sunday.

“My first Group One in Australia was for my boss, Ron Quinton, and that made it so special on a personal level. The second was for Gai Waterhouse, and was special for different reasons, but to win one here would be a career highlight,” he said.