The Green Monkey, the world's most expensive thoroughbred to sell at auction, has died in Florida at the age of 14 following a battle with laminitis.

The son of Forestry set a world record price of $16m when sold to Demi O'Byrne, acting on behalf of the Coolmore partners, back in 2006 at the Fasig-Tipton Calder Select Two-Year-Olds In Training Sale. The colt was offered that day by Hartley/De Renzo Thoroughbreds, who went on to stand The Green Monkey at their stallion division following his anti-climactic racing career.

Hartley/De Renzo, the Ocala-based bloodstock operation of Randy Hartley and Dean de Renzo, had paid 'just' $425,000 for The Green Monkey, bred by Padua Stables out of the Unbridled mare Magical Masquerade, as a yearling at the 2005 Fasig-Tipton Kentucky July Sale.

Put through their juvenile programme and catalogued to the Calder Two-Year-Old Sale the following February, he turned heads with a scintillating one furlong breeze in 9 and 4/5 seconds at the sale's under tack show.

That time, and the seemingly ease with which he did it - "I doubt if anyone has ever seen a better one-eighth performed by a two-year-old in training," commented auctioneer Walt Robertson as he opened the bidding - translated into a sale-ring frenzy which ultimately boiled down to a duel between Demi O'Byrne and Sheikh Mohammed's bloodstock advisor John Ferguson once matters soared past $3m.

Robertson eventually brought the hammer down at $16m in favour of O'Byrne after close to nine minutes of rapid-fire bidding.

Not only did the price eclipse the previous high of $5.2m for a two-year-old, which had been paid at Calder the previous year by Ferguson for a Tale Of The Cat colt, but it shattered the previous world auction record of $13.1m paid by the BBA for Seattle Dancer at the 1985 Keeneland July Yearling Sale.

"He'd better be good," O'Byrne told reporters immediately afterwards. "Time will tell."

The sale of The Green Monkey epitomised the voracious demand within bloodstock markets at that time, particularly that for the American two-year-old in training. That particular sale alone featured seven million-dollar lots out of a group of 154 sold. Incidentally, one of them turned out to be La Traviata, a fast stakes winner for Coolmore who later bred Group 1 winner Seventh Heaven.

The $16m youngster, however, did not follow suit. Turned over to Todd Pletcher and named after the Green Monkey golf course in Barbados, he went on to make three starts, none of which were successful.

He was initially hindered by a gluteal muscle injury, which delayed his debut until the September of his three-year-old career, when he ran a well-beaten third in a maiden at Belmont Park. He was later ran fourth in another maiden at Belmont and then fourth again in his career finale when switched to turf at Hollywood Park that November.

He retired with earnings of $10,440.

Hartley/De Renzo bought back half of the horse upon his retirement and it was at their base in Florida that The Green Monkey spent his stallion career at a fee of $5,000. He never covered a book greater than 12 mares following his debut season, which numbered 40, and is the sire of four black-type winners, including Monkey Business, who swept the 2015 filly Triple Crown in Panama.