Lightly-raced five-year-old Rangirangdoo takes another important step in his career in Saturday's Mackinnon Stakes with trainer Chris Waller using the race to test his credentials over 2000 metres.The five-year-old has had just 13 starts and although he is by noted sire of stayers Pentire, Waller has yet to stretch him out beyond 1600 metres.He ran second at his first Group One assignment in the Epsom Handicap (1600m) and although he loomed up to go past Rock Kingdom he went down by half a head

Lightly-raced five-year-old Rangirangdoo takes another important step in his career in Saturday's Mackinnon Stakes with trainer Chris Waller using the race to test his credentials over 2000 metres.

The five-year-old has had just 13 starts and although he is by noted sire of stayers Pentire, Waller has yet to stretch him out beyond 1600 metres.

He ran second at his first Group One assignment in the Epsom Handicap (1600m) and although he loomed up to go past Rock Kingdom he went down by half a head on the wet track.

Waller forgave him but Rangirangdoo's performance to dump Corey Brown at trackwork before the Cox Plate meeting put the weight-for-age championship out of the equation, for this year.

Rangirangdoo ran in the Crystal Mile instead and put in his most impressive performance yet when he overcame an early check to run away to a 3-1/2 length win.

Despite taking on a field of hardened Group One performers in the Mackinnon, Rangirangdoo is the early favourite but Waller is cautious.

"It's another step again," Waller said.

"He's taking on seasoned weight-for-age horses so I'm not going in there overly confident.

"I've got no doubt he will get to that level in the future but whether it's now I don't know.

"We are using the race to test him over the 2000 metres because next year's Cox Plate is the aim.

"He came through the Crystal Mile in good order and will go to the paddock after Saturday."

Waller said there were no regrets about missing the Cox Plate won by So You Think with owner Neville Morgan leaving the decision to him.

"He just made it so easy and I don't think the horse could have won the Cox Plate," Waller said.

"Owners like him just make my job easy."

Queenslander Morgan could be in for a big day with Commonage Close to bear his colours in the Victoria Derby.

The Robbie Laing-trained colt is an outsider in the 11-horse field dominated by Shamoline Warrior.

TAB Sportsbet had Rangirangdoo at $3.50 on Thursday ahead of Vigor ($6.50) and Viewed and Zipping both at $7.50.

Waller will also have a shot at another Group One on Saturday with Shellscrape to run in the Coolmore Stud Stakes and Triple Honour to contest the Group Three AAMI Business Insurance Stakes (1400m).

Shellscrape is currently a $12 chance with Irish Lights the $5.50 favourite for the Coolmore while Triple Honour is at $12 for his race with McClintock heading the market at $4.80.