A victory in NSW's longest race has proven to Goulburn's twin trainers Thunder Road has the stamina for the inaugural Jericho Cup.

The five-year-old gelding's endurance was tested even further in the 3800m Riverina Cup at Wagga Wagga with it being run on a heavy track.

But the Emma and Lucy Longmire-trained Thunder Road passed the test with flying colours and is now in third place on the Jericho Cup ballot, equal with Queensland Cup runner-up My Diamantine.

The new 4600m-race, named to commemorate a race run by the ANZACs during World War I, will offer $300,000 prize money for Australasian-bred stayers.

Points are awarded to the first three eligible horses across the line in every flat race run over 3000m or more during 2017 and 2018.

The benchmark 90 race won't be contested until November 2018 but is firmly in the sights of Goulburn duo.

Tuesday brought up Thunder Road's second win at Wagga Wagga in 10 days after he took out the 2500m prelude last week.

"He's a very clean-winded horse, very easy to keep fit," Emma said.

"He only weighs 420 kilograms and just skims over these heavy tracks."

Cranbourne-trained Rock Icon, who finished two lengths behind Thunder Road in the Riverina Cup, is now on four points for the Jericho.

JERICHO QUALIFYING LEADERBOARD

* 10 points - Bayanova (M Kent)

* 7 points - Prize (S Wilde)

* 6 points - Thunder Road (E & L Longmire), Spur on Gold (G Young), Amortise (N Blackiston), Zarantz (G & A Williams), My Diamantine (B Smith)