Veteran Steel Zip's zest for racing continues to amaze even his trainer and jockey ahead of his attempt to win his sixth stakes race.

The rising nine-year-old will step up to 1600 metres for the first time in 15 months when he tackles the final stakes race in Brisbane this season, Saturday's Listed Tattersall's Mile at Doomben.

Steel Zip has been in good form since resuming with a third in the Ipswich Eye Liner Stakes, fourth in the Caloundra Glasshouse Stakes and third in the Ramornie Handicap at Grafton.

Steel Zip, whose career began in 2010, will be having his 74th start, his 44th run in a feature race and his 28th visit to Doomben but trainer Pat Duff said that was only part of the story.

"Obviously with older horses you always take them as a day by day proposition. But he shows me no signs that he has lost his zest for racing," Duff said.

"Brad Stewart rode him for the first time in a while in the Ramornie and was amazed with him. He told me Steel Zip felt no different to ride than when he was a four-year-old."

Duff is confident Steel Zip will have no trouble stepping up to the metric mile on Saturday.

"If anything this campaign he has been going better than usual," he said.

"He has won at the Doomben 1600 metres. Probably one of his best runs was a fifth in the Queensland Guineas which he possibly should have won.

"I know that was a fair while ago but he has usually raced well at 1600 even if he doesn't win. He has had a solid build-up in trials and races."

If anything is worrying Duff it is Steel Zip's rapid rise in weights.

"His weights have been going up and down like a yoyo. He had 55.5kg in the Ramornie and 56 in the Glasshouse now he has 59," Duff said.

"But my father once told me when you are confused about the weights look for the one who looks slaughtered as it usually wins. Hopefully, that will be the case on Saturday."

Win lose or draw, Steel Zip owes nothing to Duff and his family who race the grey.

"Steel Zip cost us only $13,000 as a yearling and has now won $915,000. But more than that he has given us a lot of pleasure," Duff said.