A four-foot concession by Western Australia’s Amanda Gan has guaranteed Queensland a place in the final of the Australian Interstate Teams Matches at Southport Golf Club.

Showers filtered through Southport continuously on day two as WA, New South Wales and South Australia all tried to revitalise their hopes of qualifying for Wednesday afternoon’s final.

Queensland held off a spirited NSW effort in Round 3 to win 4.5-3.5 as WA halved their clash with the undefeated Victorians and South Australia accounted for Tasmania.

That set up a mouth-watering Round 4 on Tuesday afternoon as the home state went up against WA, Victoria and South Australia faced off in a virtual do-or-die clash and NSW sought to keep their title defence alive against Tasmania.

The Blues defeated Tasmania 6-2 and the big guns for Victoria all fired in their 7-1 victory over SA, leaving Queensland and WA to dictate the leaderboard heading into the final day.

Projected wins see-sawed throughout the afternoon such that a 4-all halved match seemed the likely outcome.

Seeking her second win of the week in the second-to-last match, Justice Bosio had her hands full with Gan as Queensland’s No.1 male player Quinn Croker squared off against in-form West Australian Jordan Doull.

Doull would claim his third win for the week 1 up on the 18th hole but an extraordinary show of sportsmanship from Gan saw her lose 2 down to Bosio, enough to secure Queensland the full point, 4.5-3.5.

With one round to play before the final, Queensland is on 3.5 points followed by Victoria on 3 points, leaving NSW (2) and South Australia (2) to pray for a miracle to edge the Victorians for the second spot in the final.

One-up playing the last, Bosio lagged her birdie putt down to four feet after Gan left her putt for birdie some 15 feet short.

Rather than attempt to make her par putt and apply pressure to Bosio, Gan conceded the hole to her Queensland opponent.

“I was asking Asha (Queensland manager Asha Flynn) for some scores, score updates throughout the round to kind of know what was happening,” said Bosio.

“I knew that I needed to at worst square my match so it’s really good to get a win.”

Only three players have won all four of their matches to date, and all come from the powerhouse Victorian team.

Captain Jazy Roberts and Asia-Pacific Amateur champion Jasper Stubbs continue to lead from the front while 15-year-old Amelia Harris extended her extraordinary run in Interstate competition.

Debuting in the senior Interstate as a 13-year-old for the champion Victorian team in 2022, Harris defeated Amanda Gan 2&1 in Round 3 and then accounted for previously undefeated South Australian, Amelia Whinney, 5&4.

Five-up through five holes, Harris said it is her short game that is proving to be a strength on the twisting Southport layout.

“I made most of my up-and-downs today, which was really good,” said Harris, who won the third hole when she got up-and-down from the left of the green and Whinney three-putted.

“I feel like I have pretty good course management and coming from Cairns, I’m pretty used to the grain and a bit of water and tight fairways.”

A half-point against Tasmania will be enough for Victoria to play their way into the final while both South Australia and NSW need Tasmania to conjure the mother of all upsets and record similarly dominant victories themselves.