Chris Waller is trying out a new tactic with triple Group 2 placegetter Waterford.

Waterford has showcased himself as a black-type winner-in-waiting with a multitude of Group and Listed placings, yet a stakes race success still eludes the five-year-old.

That missing piece has prompted trainer Chris Waller to rethink his approach this preparation and as a result, Waterford will extend to 2000m for the first time in the Listed W J McKell Cup at Rosehill on Saturday.

The gelding's best form has historically been at the start of his campaigns – four of his five wins have come first or second-up, as have five of his six minor placings.

Those statistics have led the stable to think the gelding may have found his level over races up to a mile and could benefit from stepping out in distance.

"We spoke about it early on in the prep," Waller's assistant Charlie Duckworth said.

"He always comes back and looks like he is going to win something decent, and he seems to be sharp over those 1400-metre and mile distances, but then he plateaus further into his prep.

"If he is a horse that can get 2000, or even 2400, that opens up a lot of other avenues for him, because over that mile range, he might have just hit his mark."

Waterford's only other attempt beyond 1600m yielded a closing fifth in the Five Diamonds (1800m) and the gelding has been racing well this campaign, including a narrow and unlucky second in the Scone Cup.

He will be one of four McKell Cup runners for Waller, who has surprisingly only captured the middle-distance feature once before with Skyman two years ago.

Former Irish mare Foniska has been scratched from Brisbane and will take her place for the stable, along with seasoned campaigners Bold Mac and Lord Ardmore, who both need to rediscover some of their old form.

Duckworth expected Lord Ardmore to strip fitter with the benefit of two runs under his belt, while Bold Mac turned in his best performance in some time with a fast-finishing fourth to Ruby Flyer over 1600m at Randwick last start.

"Lord Ardmore needs to lift a little bit to find some form," Duckworth said.

"He is third-up, so he's entitled to improve, but he needs to at the same time.

 "Bold Mac was a little bit better last start and we're hoping a bit of weight relief can help get him back into some form so we're claiming on him."

Waller will have up to 26 runners across Saturday's 11-event card and outside of his feature race chances, the lightly exposed Pure Alpha shapes as a horse to watch in the Racing For Good On July 13 Handicap (1400m).

The three-year-old has been patiently handled to win two of his four starts and the stable is keen to see how he handles the rise to Saturday company.

"It's a step up in grade Wednesday to Saturday, but at this time of year it's less of a jump than at other times," Duckworth said.

"When he first came over from New Zealand he was light as a feather and he has taken a long time to mature, but he is finally coming of age.

"He could be a horse that ends up kicking on right through the grades and being pretty handy."