The 31-year-old is the sole surviving descendant of Greek shipping magnate Aristotle Onassis who, in 1968, married Jackie Kennedy, widow of the American President John F. Kennedy.

The sale of MHS Going Global is believed to have been negotiated for the past two weeks, but was only concluded following a full veterinary examination.

Onassis represented Greece at the 2013 European Championships in Denmark and at the following year’s World Equestrian Games in France. 

MHS Going Global was bred in County Kilkenny and first appeared on the Irish show jumping circuit with Francis Connors, before Broderick took over the ride in the summer of 2011.

A superb record as a clear round jumper in various Grand Prix events and Nations Cups saw Broderick and Going Global selected as Ireland’s sole individual combination for Rio, where he dropped out in the second qualifier after finishing equal 50th.

Broderick said in a statement on Facebook that he and Going Global had shared an "unbelievable journey, from novice classes in Ireland to making dreams come true with Olympic Games and Nations Cup wins".

"He has given my family, friends, owners and the Irish horse world something to be very proud of and thank you to everyone who has been supportive of us along the way," added the 31-year-old.

"He was part of the family here at Ballypatrick and like a best friend to me.

"He will be hugely missed but it was a logical decision to sell him in the height of his career.

"I would like to wish his new owner Athena Onasis all the luck with him and a big thank you to Lee Kruger for the opportunity to ride this great horse."