Young stallion Unencumbered has died after suffering complications from throat surgery.

The six-year-old had been diagnosed with chondritis, a progressive inflammatory condition of the throat.

"Unencumbered was a special horse with such a great personality, everyone that has ever come in contact with him will miss him terribly," Three Bridges Thoroughbreds proprietor Peter Liston said.

"He put his trainer Bjorn Baker on the map and his memorable win in the 2014 Magic Millions 2YO Classic at the Gold Coast, with Nathan Berry in the saddle was a fairy tale result for his big group of owners."

The Magic Millions was the biggest win in the career of the late Nathan Berry, the identical twin brother of fellow jockey Tommy Berry.

Nathan Berry died in April 2014 from Norse syndrome, an acute form of epilepsy.

Baker posted a tribute on Twitter.

"Gutted to hear of Unencumbered's passing this morning. He was a wonderful horse who holds a special place in my heart - not just because of his feats on the racetrack and the breeding barn, and his partnership with my mate Nathan Berry but also because he was such a gorgeous specimen loved by his owners, a firm favourite with the staff and such a laid-back dude. Condolences to the team at Three Bridges, and all who had close links with him. We'll all miss him," he said.