BRISBANE Jan 30 AAP - Hi Son's trainer David Kelly has warned punters to ignore the four-year-old's last start failure ahead of his staying test at Doomben on Saturday.

Hi Son was entered for a Benchmark 85 race as well as the Open Hcp (2120m) at Doomben, but Kelly was keen to test his pet theory about the galloper in the better company.

The Gold Coast trainer has long believed Hi Son, who has not won beyond 1600m or raced past 1800m, is a potential top-line stayer.

Hi Son was only 10th in the Magic Millions Stayers Cup (1800m) on January 11 but Kelly warned it would be folly to take any notice of the run.

"He got his tongue over the bit in that race. His previous form gives him a real chance Saturday's race," Kelly said.

Hi Son was a Doomben restricted class winner over 1615m three runs back for apprentice Rikki Jamieson.

She is back on Hi Son on Saturday after Michael Cahill rode him in the Magic Millions Cup.

"Rikki will claim 3kgs and he will get in under the limit on just 53kgs," Kelly said.

Kelly's high opinion of Hi Son was confirmed last winter when the gelding ran third to Proverb in the Group Three Gunsynd Classic (1600m) for three-year-olds at Doomben before he was sidelined.

"He had to undergo surgery for a minor hock injury to a back leg after that run and missed the rest of the winter," Kelly said.

Hi Son also ran fifth as a two-year-old behind Sizzling in the Group Two BRC Sires Produce (1400m) when caught on the heaviest part of the track.

Kelly, a former top jockey, has been doing a good job with his team after taking out his trainers' licence 12 years ago.

His best gallopers to date have been Poetic Papal who beat Takeover Target to win the Group Three Carlton Draught Stakes (1200m) and Kryptelon who won the Listed Gai Waterhouse Classic.

But he believes Hi Son can prove to be his best galloper in coming months.