Just six months earlier, he had jumped a historic double clear to win the Aga Khan Nations Cup for Ireland on his home turf in the RDS Dublin, and jumped clear to win the Nations Cup in Hickstead.
The stallion (by Diamant de Semilly) was a real family horse, owned by Clem and his mother Maureen and stabled only steps from the back door of the home Clem shares with his wife Stacey and son Louis.
Speaking at the time, Stacey said Pacino, who was known as 'Al' at home, had "all four hooves firmly inside our house and our hearts".
This week, Clem said he and his family were "dealing" with their loss, although they would never really get over it.
"Losing Pacino was awful because he was the kind of horse you wait all your life for. When you think of what he achieved as an eight-year-old, it was more than you would expect from a 10-year-old horse," explained Clem.
"But he was also a business all on his own. He should have been covering 150-200 mares this year and for many more years to come.
"His death was like a good business burning to the ground."
It is believed there are less than 200 Pacino progeny on the ground in Ireland and Europe because the young sire had been focused on his competition career up to his premature death.
The Pacino colt bought by Clem was one of 12 elite show jumping foals auctioned at the Irish Breeders Classic sale in Barnadown, Co Wexford last weekend.
The second highest price of the day was €9,500 for a filly by My Lord Cathargo. The filly was bought by Surrey-based Irish rider Brian Cassidy on behalf of Al Shir'aa Stables, which has yards in England and Abu Dhabi.
Cassidy also bought a second filly, by Voltaire, for €7,000 for himself.
"Hopefully I will be able to produce her up the ranks in the future," said the rider, who is based in the Al Shira'aa yard in Guildford and is on crutches after having bones fused in his foot.
The Voltaire filly is out of the same dam as Brian's promising young show jumper CSF Vendi Cruz, who this year competed at Lummen in CSI1* young horse classes.
A colt foal by the famous Irish Sport Horse Flexible, the 2012 FEI Show Jumping World Cup champion, sold for €9,000 to Julie Ann Gaffney of Kildare Equestrian Centre, while colt foals by Plot Blue and Chacco Blue sold for €6,000 and €5,000 respectively.
Interestingly, the Plot Blue colt was produced by embryo transfer from a dam, MHS La Scala, who jumped in the show at the same time as her foal was being sold.
Meanwhile, Co Tipperary rider Greg Broderick swept to victory in the main class of the show, the Irish Breeders Classic Final, on board the promising five-year-old mare Arraghbeg Clover.
First staged in Ireland last year, the Breeders Classic is the richest young horse class in the world, with a massive €50,000 prize fund on offer to the best five- and six-year-old horses born in Ireland.
Broderick, whose sister Cheryl and father Austin run a major breeding operation near Thurles, came up with the idea for the elite foal sale last year.
The young rider and Arraghbeg Clover represented the Irish Sport Horse studbook in the FEI World Breeding Jumping Championships for Young Horses in Lanaken, Belgium last week.
Meanwhile, Cavan Horse Sales is to host its Elite Foal Sale this Thursday, September 26, with 31 progeny of high-profile sires being presented.
The sale takes place during the prestigious annual Cavan Indoor Championships week-long show.
The catalogued foals all come with an impressive background on both sides, with many well known and famous sires on show including Sir Shutterfly, Plot Blue, Ustinov, Cardento, Arko III and Flexible to name a few.
This, coupled with an impressive dam line, is sure to attract the eye of many purchasers.
All dams have competed themselves or have some illustrious siblings and/or progeny with proven records, giving the foals solid backgrounds. When matched with a notable stallion line, this provides a dependable breeding base to start with.
The catalogue can be viewed online at www.cavanequestrian.com which includes details and photographs of all foals. Alternatively, contact Cavan Equestrian Centre on 049 4332017.
Viewing of foals will commence at 6pm, with the sale commencing at 7pm.