Show Stealer will be looking to tear up Udontdodou's script

Guest, who rode Red Marauder to victory in the monsoon Grand National of 2001, has targeted this prestigious race since he acquired the sprinter at Newmarket’s sales.

It will not be easy – one of the biggest threats in this six-furlong contest for three-year-old sprinters is the well-regarded Show Stealer who is trained by Guest’s elder brother Rae.

However, Udontdodou is a horse on the upgrade. Three promising runs last season, culminating in a close second at Doncaster’s season-ending meeting, have been followed by impressive wins this year at Thirsk and Windsor under former champion conditional jockey Jason Hart who is, once again, entrusted with the riding responsibilities.

Yet there was an element of luck about how Guest acquired the horse. Originally sold for £76,000, the successful bidder did not foot the bill and the colt, after several weeks at a livery yard, looked on the tubby side when sold to the trainer’s wife Alison for around £20,000.

However, Guest, who has around 30 horses in training at his Ingmanthorpe yard near Wetherby, spotted similarities with Barnet Fair who just failed to make the cut for the 2012 renewal of this race, which is one of the highlights of the Macmillan charity day that York has staged so successfully for the past 46 years.

“He must have been well thought of to go for that money in the first place,” Guest told The Yorkshire Post.

“All he did at the livery yard was eat and sleep. You can imagine how fat he was. He was this fat, waddling thing, which no one wanted, but I thought he had a lovely pedigree so took a chance.

“He’s a laid back horse, but he takes everything in his stride. He’s turned out for four hours a day, he goes on the horse walker and does a couple of canters.

“This has been the aim for 10 months. We had a horse called Barnet Fair who just missed the cut – I was certain he would win – but I think this horse has a bit more quality.

“A little bit of rain has been music to our ears. I’m sure he would go on fast ground, but he’s a big bull of a horse and it’s all about minding him.

“For a little stable like ours, we’re not going to get many horses of this calibre so conditions are important.”

This race was won 12 months ago by Henry Candy’s Twilight Son, who then went on to win Haydock’s Group One Betfred Sprint Cup.

Given the contest’s prestige, a bold show by Udontdodou could see the horse sold next week – the sprinter is entered in the Goffs sale in London that coincides with Royal Ascot.

First there is the small matter of beating a quality field that includes the aforementioned Show Stealer who won at Newmarket last month.

The sibling rivalry between the Guests is a friendly one – their family is steeped in racing and their sister, Lady Jane Cecil, is the widow of Sir Henry Cecil.

“We get on very well,” said Guest, whose assistant trainer is former jump jockey Shane Byrne.

“Rae’s best qualities as a trainer are patience, attention to detail and his placing of horses in races.

“If he wins, I will be thrilled for him, and the other way round.

“He won’t thank me for saying this, but we’re 15 years apart. He was more of a father figure to me than a brother because he had left home when I was born. I think we missed out on the sibling rivalry. Now we’re older, it’s enjoyable.

“As for Jane, I’m baby brother so she will be rooting for me.

“Seriously, she will be equally thrilled if either of us wins – just like we were when she was with Sir Henry during the Frankel years and when winning Group One winners in her own name with Noble Mission.”