Ruby Walsh: Why Aidan O'Brien opted to put all his Derby eggs in the Bolshoi Ballet basket

Bolshoi Ballet ridden by Ryan Lee Moore. Picture: Brian Lawless/PA Wire.

On Wednesday afternoon Aidan O'Brien dropped the bombshell that Bolshoi Ballet would be his sole runner in this afternoon's Cazoo Epsom Derby.

Only last Monday, he had left six colts in the race at the forfeit stage, which wasn't for free. I didn't expect all six to be declared on Thursday morning, but four or maybe five seemed likely. One was not even a number I considered.

Aidan doesn't send one colt out on his own at Epsom; he always covers the bases and has backup. After all, this is the Epsom Derby, a race he has won eight times and the race for three-year-old colts.

In recent times, opinions have been divided as to the actual value of winning the Derby at Epsom. Some people have questioned if it still adds to the stud value of the winner but not Aidan or his bosses at Coolmore.

They have arguably been the race's biggest supporter and still see it as the acid test of a potential stallion, so why now only run one? Obviously, Bolshoi Ballet is the favourite but why leave second favourite High Definition at home?

What if Bolshoi Ballet has an off day? Why not run High Definition as a worthy backup? Did he not want a repeat of High Chaparral and Hawk Wing? Maybe not, but why not declare at least three so you can tactically control the race in a way that suits you?

He'd have two potential pacesetters, but with only Ballydoyle knowing which one would go forward and leaving some doubt in the minds of the others. After years of using pacemakers, why now is he sending Bolshoi Ballet out on his own to be at the mercy of everyone else's tactics?

Maybe he didn't want a repeat of Serpentine last year; after all, Aidan's job is not just to win the big races but also to make stallions for the Coolmore empire.

That said, a true champion wasn't caught out by Serpentine, so that can't be the reason either because, on reflection, Coolmore were lucky Aidan ran so many last year.

It was a classic example of throwing enough darts, and one might hit the bull's eye.

So why has he put all his eggs in the Bolshoi Ballet basket? High Chaparral and Hawk Wing took each other on, Camelot had Astrology to go a good gallop, Australia had King Fisher, who he didn't end up needing, but he had him.

Ruler Of The World was one of five Ballydoyle runners, Wings of Eagles one of six, Anthony Van Dyck one of seven, and Serpentine one of six.

They are just the Derby's Aiden won, bar one, the most important one. Because when Aidan won his first Derby in 2001, 20 years ago, Galileo tackled Epsom alone. He was the most important because he ended up being the foundation of what Aidan O'Brien, Ballydoyle, and Coolmore have become.

His daddy, Sadler's Wells, may well have helped start the empire, Danehill carried it along, but Galileo has taken it to a whole new level.

With him at stud in Tipperary, the Coolmore team set about buying all the best broodmares they could find for him to service, and the offspring they have produced has been incredible.

Last June, he surpassed Danehill as the winning-most sire of individual Group 1 winners.

He has had a little more time than Danehill to achieve it, as poor old Danehill suffered a fatal injury in a paddock at the age of 17, but Sadler's Wells made it to the age of 27 as a working stallion.

Remarkable, really, but here comes the catch for Coolmore: Galileo is now 23, and whatever you look at it, has already covered far more mares than he is going to cover in the future.

Commercially time is not on his side, and an heir needs to be found, making the splitting of Bolshoi Ballet and High Definition credible in an attempt to make another make a high-end stallion prospect for Coolmore.

Neither solves the imminent breeding issues within the stud as both are sons of Galileo, and an outcross will still be required for all their own top-class daughters of Galileo.

However, from a business point of view, a champion 3-year-old colt is still of massive value, and maybe this is why Aidan is only firing one bullet today.

He said High Definition would wait for the Curragh and have a shot at the Irish Derby, suggesting he and Bolshoi Ballet go different routes. Until a possible meeting in France on Arc day or maybe never if one goes to Ascot for their Champion Stakes or even the Breeders' Cup.

That's my theory for Aidan's Derby decision. Run Bolshoi Ballet at Epsom, the Eclipse at Sandown over 10 furlongs in July, the Juddmonte at York in August, and the Irish Champion Stakes at Leopardstown in September.

A horse with the stamina to win at Epsom and the speed for genuine Group 1s at 10 furlongs, by Galileo, would be an easy sell for a high stud fee as a stallion.

That route would leave a path along the lines of the Irish Derby, the King George at Ascot, and the St Leger at Doncaster for High Definition.

Last year's star mare Love could go a separate path too, starting in the Prince Of Wales's Stakes at Royal Ascot, the Pretty Polly at the Curragh, the Nassau at Goodwood, and the Yorkshire Oaks.

Divide and conquer to achieve the maximum, but today's dividing is most relevant right now.

Aidan has said and will repeat that the 'lads', his bosses at Coolmore, make all these decisions.

He will credit everyone who has even looked in over Bolshoi Ballet's door if he wins but make no mistake here, if Aidan didn't believe Bolshoi Ballet to be the chosen one, he wouldn't be flying solo at Epsom.

I'm reading between the lines with all that I have written and taking note. I hope you do too.