Paul Nicholls admitted his "sadness" after Kauto Star's time at his Ditcheat yard came to an abrupt end on Tuesday.
The winner of five King Georges and two Cheltenham Gold Cups had been officially retired in late October and was expected to remain at Manor Farm Stables in Somerset until Boxing Day, when he was due to parade at Kempton.
Owner Clive Smith had announced on Monday that the 12-year-old would be moving away to be prepared by European bronze medalist eventing rider Laura Collett and long-time Great Britain manager and coach Yogi Breisner for a new career in the world of dressage - a decision not popular with Nicholls and his staff.
The winner of 19 races for the champion trainer, including four Betfair Chases and two Tingle Creeks, Kauto Star had been with Nicholls for eight years and was invariably ridden by his head lad Clifford Baker.
Nicholls told his Betfair column: "It is with great sadness that I have to report that Kauto Star has left the yard for the last time. It has been no secret that Kauto's future has been a great source of debate since we announced his retirement. And, to be brutally honest, this morning I felt the time had finally come for me to take control of the situation, and to start making the decisions.
"Now, I am fully aware that Kauto is Clive's horse and he can do as he wishes, even though I would personally have loved Clifford to have looked after him for the rest of his years. But what upset me and my team here is when Clive announced that he had spoken to experts about the horse's future - but failed to consult and listen properly to the team that had looked after him here for the past nine years. That really upset us."
Nicholls went on: "So we had a team meeting here this morning. And after listening to everybody involved - there were about six of us in the meeting - I rang up Clive, said I don't want to fall out, but we think it is in the best interests of everybody concerned to take Kauto to Yogi Breisner's this afternoon so that he could start his new career in the dressage field as soon as possible.
"Which we did with the saddest of hearts. But I like to think with a lot of dignity, too. And, yes, there were plenty of tears too. He was a member of the family here at Ditcheat, and we will all miss him so much. I would just to like say that it was a privilege for us here at Ditcheat to train the horse. Good luck, old boy. You were the best - and deserve the best."
Collett, 22, who is an aspiring Olympian based at the Membury Estate in Wiltshire, tweeted: "I feel very privileged and extremely honoured to have been asked to ride Kauto Star. I will be working closely with Yogi to give Kauto Star the best chance of a second career in dressage."
She later added: "Kauto Star has arrived safe and sound. Had a nice roll, now happily munching on his hay!"
27 September 2016Charlie Fellows pulls off Fairyhouse coup with big gamble Moonlit Show
Fair Eva conqueror Spain Burg to go under the hammer
Adrian Keatley checks in for Concorde Stakes with Jet Setting
Brian Meehan plays waiting game with Cambridgeshire hero Spark Plug
Dandy Nicholls leaning towards Ascot with white-hot sprinter Kimberella
Jim Bolger to resist Dollar cash with Dundalk-bound Qatari Hunter
Minor setback forces Magical Memory into early winter break
Ascot still top of Almanzor agenda despite featuring in Arc field
Trip To Paris in contention for Cadran outing at Chantilly
Frankie Dettori hunting Arc mount after Fascinating Rock is ruled out
'He was nearly picking them up and putting them over the line'
Waterlogging claims Ayr card
Scrutineer floors Danzeno in Hamilton feature
Marracudja gets Paul Nicholls and Ditcheat Thorougbreds off to winning start
Long Distance Cup remains on the agenda for Forgotten Rules
Munster National to honour memory of JT McNamara
Shalaa pencilled in for weekend return at Ascot
'Magnificent Seven' heaven sent for proud Frankie Dettori
Henry Candy sets sights on Chantilly with Limato
Alice Springs and Persuasive in line for rematch in Sun Chariot at Newmarket
Christophe Soumillon receives Silverwave Arc call-up at Chantilly
26 September 2016Precautionary inspection called for Ayr Tuesday card
Colin Tizzard delight at arrival of horses for Alan and Ann Potts
Only Mine signed off for the season by Joe Murphy
Charlie Fellowes hopes Moonlit Show can shine at Fairyhouse
Jarlath Fahey to delay Cesarewitch call with Jennies Jewel
Willie Mullins wants swift resolution to Faugheen 'investigation'
Salisbury Wednesday fixture loses one-mile race
Hamilton Monday card gets go-ahead
Setback rules La Cressonniere out of Prix de l'Arc de Triomphe
Dermot Weld has Tuesday workout plans for Arc hope Harzand
Jim Bolger has Gold Cup dreams for Twilight Payment after Loughbrown Stakes
Aidan O'Brien lines up three-pronged attack on Arc
Capri continues Beresford Stakes domination for Aidan O'Brien
Happy days for Aidan O'Brien in Renaissance Stakes
Classic-winning trainer Tommy Stack to retire at the end of the year
Eziyra puts Classic claims with Curragh success
Wesley Ward finds possible reason for Lady Aurelia Newmarket reverse
25 September 2016Rain threat to Hamilton card on Monday
Dermot Weld has Tuesday workout plans for Arc hope Harzand
Ed Dunlop plays the long game with Red Verdon
Richard Fahey retains faith in vanquished Frankel filly Queen Kindly
One-mile race at Salisbury in jeopardy on Wednesday
Owen Burrows calls time on Massaat season
Henry de Bromhead has chasing in mind for Identity Thief
Ed Vaughan heads to Ascot with Mehronissa
Arc favourite Postponed pleases in Saturday workout
Spark Plug fires up for Cambridgeshire glory at Newmarket
The Last Lion sparks Group One celebrations for birthday boy Joe Fanning
Cheveley Park first for Aidan O'Brien as Brave Anna tops Lady Aurelia
Hugo Palmer has Derby dream for Best Of Days
Paul Hanagan speculation news to me - Angus Gold
Capri leads Aidan O'Brien's four-strong challenge on Beresford heat
Perle De La Mer seeks to sparkle in Park Stakes date
Forgotten Rules aiming to issue Loughbrown reminder
24 September 2016Waterlogging claims Roscommon card
Hugo Palmer retains faith in Escobar despite Newmarket eclipse
No retirement plans for Gordon Lord Byron ahead of Renaissance run
Jack Kennedy sidelined after Downpatrick fall
Fair Eva grounded by French flyer Spain Burg
Cougar Mountain peaks at Newmarket for Aidan O'Brien and Ryan Moore
Newmarket winner Journey takes familiar route towards Ascot
John Gosden has the last Laugh at Newmarket
Bronze Angel bids for third Cambridgeshire gold in vintage renewal
Best Of Days and Hugo Palmer ready for Royal rumble at Newmarket
Blue Point and Mehmas face Middle Park rematch
Wesley Ward expecting Lady Aurelia to show her best in Cheveley Park test
Colm Murphy announces shock retirement news