David Hayes has paid tribute to Better Loosen Up, declaring there hasn't been a finer racehorse pass through his famous stables.

An Australian Horse of the Year, Better Loosen Up died of heart problems, aged 30, while spending his retirement at Living Legends on the outskirts of Melbourne.

First trained by Les Theodore at Berrigan in the NSW Riverina, Better Loosen Up had a stint with Bart Cummings in Sydney before he was sent to Lindsay Park to be trained under the guidance of Hayes' father Colin.

Better Loosen Up provided Hayes with the perfect start to his career after his father's retirement from training.

In 1990 Better Loosen Up won the Feehan Stakes, Turnbull Stakes, Cox Plate, Mackinnon Stakes and Japan Cup.

He returned to racing during the 1991 autumn carnival to claim the Blamey Stakes and Australian Cup.

"The whole Lindsay Park team loved him and he was the best horse that I've had something to do with," Hayes said.

"He was an Australian horse of the year, won an international race that no other Australian horse has won and was also successful in a Cox Plate.

"He was just fantastic."

While the Japan Cup rates as a career highlight, Hayes said two races that stood out were his Cox Plate and Australian Cup victories.

"The Cox Plate was probably his best win in Australia as he gave Stylish Century 30 lengths and wore him down," Hayes said.

"But the Australian Cup, which he won by five-and-a-half lengths against some big names, that was pretty special too."

Better Loosen Up bowed a tendon while getting ready for the Sydney autumn carnival.

"Unfortunately he was in career-best form when he broke down," Hayes said.

Better Loosen Up was retired after finishing second in the RN Irwin Stakes at Morphettville in February, 1993.

FACTBOX

* Better Loosen Up: Sire - Loosen Up / Dam - Better Fantasy

* Winning trainers - Les Theodore, Bart Cummings, Colin Hayes and David Hayes

* 45 starts: 17 wins - 9 seconds - 3 thirds

* Prizemoney: $4,773,970

* 8 Group One wins: Honda Stakes (now Emirates), Kingston Town Stakes, Railway Stakes, Segenhoe Stakes (now Ranvet), Cox Plate, Mackinnon Stakes, Japan Cup and Australian Cup