The racing career of weight-for-age warrior Black Heart Bart has come to an inglorious end.

A six-time Group One winner, Black Heart Bart finished a long way down the course in the Hyperion Stakes over 1600m at Belmont in Perth on Saturday.

The rising 10-year-old was beaten almost 30 lengths but bled from both nostrils in what trainer Lindsey Smith had described as a make-or-break race.

Smith took charge of Black Heart Bart when the veteran came out of retirement after winning five times at racing's elite level for disgraced trainer Darren Weir.

In one of the shocks of the 2019 Victorian spring carnival, Black Heart Bart won the Group One Underwood Stakes at Caulfield, his second success in the race, at triple-figure odds.

He almost did it again at his next start when beaten a nostril in the Caulfield Stakes before finishing ninth in the Cox Plate.

But Black Heart Bart's loss of form has been sudden with two unplaced runs during the Melbourne autumn carnival before a return to Perth racing where he first made a name for himself.

Smith described Black Heart Bart "as a true champion", saying the winner of 17 races had earned a deserved retirement.

Black Heart Bart raced 62 times and collected more than $4.8 million in stakes.

His Group One tally also included The Goodwood in Adelaide but he excelled at Caulfield where he also won the Memsie Stakes, the CF Orr Stakes and the Futurity Stakes.

The Hyperion was won by the in-form Adam Durrant-trained mare Perfect Jewel who produced a withering finish to remain unbeaten this preparation.

Smith sent out another Group One winner in the race with Humidor also finishing unplaced - almost eight lengths from the winner.

Responsible for giving Winx a fright when runner-up in the third of the champion mare's four Cox Plate wins, Humidor would also appear to be at a career crossroads as a rising eight-year-old.