Dato Tan Chin Nam has paid tribute to his long-time friend Bart Cummings who trained four Melbourne Cup winners for the Malaysian businessman.

Cummings, who died in the early hours of Sunday morning, trained Think Big to win the Cup in 1974 and 1975, Saintly (1996) and Viewed (2008) for Dato Tan, the man who stuck with him through the bad times as well as the good.

When Cummings almost went bankrupt after the collapse of the Cups King Syndicate, Dato Tan bought his property Princes Farm, and later sold it back to the trainer when he was solvent again.

Through his Australian manager, Duncan Ramage, Dato Tan said the two were more than owner and trainer.

"He has done more than enough for me in his life. We have had our differences but at the end of the day bygones are bygones. A friend in need is a friend indeed and Bart Cummings is a great mate of mine," he said.

Ramage, whose association with Cummings began when he came from England and started riding trackwork at Randwick, acknowledged the trainer as a legend.

"Bart was a living legend and a national treasure. He no longer lives but the legend will live on. He was a legend to me and no person has been a greater influence in my life. I had the honour to spend several decades in his close attendance at work and sometimes at play," Ramage said.

Racing NSW chief executive Peter V'landys described Cummings as a great Australian.

"Australia is today mourning the passing of one its treasures," V'landys said.

"Bart was a legend in every sense of the word, not only in sport, as he was a great Australian.

"Bart's career spanned six decades and he was a household name.

"Bart was always in a league of his own. His larger than life character and sharp wit will be sorely missed. Bart goes down as a legend in Australian sport, up there with the great Don Bradman.

The Hayes family racing dynasty is one that can be compared to the that of the Cummings clan.

The late Colin Hayes and Bart Cummings trained alongside each in Adelaide where they were fierce rivals until Cummings moved interstate.

Both were among the inaugural inductees to the Australian Racing Hall of Fame in 2001.

They have passed on their legacy and Colin's son David Hayes is now one of Australia's most successful trainers and also in the Hall of Fame.

"He was a very fierce competitor with my father and of course I did a lot of competing against him in the last 25 years," Hayes said.

"He's really set the bar and we're all trying to jump over it."

Englishman Nigel Blackiston ran Cummings' Melbourne stable and experienced his biggest thrill when he got to stand beside 1991 Caulfield and Melbourne Cups winner Let's Elope after her big wins.

Blackiston is now a successful trainer in his own right and hopes to get Let's Make Adeal, a grand-daughter of Let's Elope, to this year's Cup.

"He was a great teacher, a master trainer and obviously it's very sad the racing industry has lost one of the all time greats, but at the end of the day the Cummings family has lost a husband, a father and a grandfather," Blackiston said.

"I've had some great mentors ... his sheer knowledge and what he's achieved as a trainer will never be passed again.

Chris Waller has just celebrated his fifth Sydney training premiership for a season that also yielded 14 Group One wins.

He said the enormity of Cummings' achievements were mind-blowing but more importantly for him as an up-and-coming trainer was the chance to learn from an old hand.

"If you had time to have a general chat with him, he always had time for you," Waller said.

"Racing needs so many positive things and Bart was the ultimate representative for the sport.

"I can't even imagine his record of Group One wins. We had a good year last year but Bart was an absolute freak."

Flags on racecourses around the country are at half-mast including those at Randwick in Sydney, Cummings' training base.

"Bart Cummings stands above all in the history of Australian racing for his achievements on the racetrack," Australian Turf Club chief executive Darren Pearce said.

"His skill with horses was matched by his extraordinary personality, and a great wit that was so revered by Australians who might not normally be involved in racing.

"We thank and honour Bart Cummings as a legend of our sport and a great Australian."

There is a statue of the great trainer at Flemington, the home of the Melbourne Cup which Cummings won 12 times.

Racing Victoria chairman, David Moodie, paid tribute to the legacy of Cummings.

"Bart Cummings has left an indelible mark on the Victorian racing industry having achieved an unparalleled record in our biggest races and his memory will live long as part of racing folklore," Moodie said.

"Bart's horsemanship and training achievements were both respected and admired by his peers and he transcended racing to capture the hearts and imagination of the Australian public."

On October 4, the Bart Cummings, a 2500m handicap, will be run at Flemington and for the first time, the winner will fittingly gain entry to the Melbourne Cup.

Racing Australia chairman, John Messara, also acknowledged the contribution Cummings made in bringing racing to an audience that might not otherwise embrace the sport.

"The name JB Cummings is forever etched in racing history. Bart will always be spoken of with wonderment at his achievements," Messasra said.

"Bart had a unique impact on the general public with his laconic wit and big-race victories. He brought racing to the wider community."