Wellington twins Peter and Thomas Spearman-Burn (20) and Nelson brothers Sean (21) and Blair (19) Riordan are in the field for the South Island strokeplay championship starting at the St Clair Golf Club today.
All four have high hopes but most eyes will be on Peter, the defending champion and 2009 New Zealand amateur golfer of the year.
He has never played in Dunedin but still holds the course record at Arrowtown's Millbrook course with the 10-under-par 62 he shot in New Zealand Open qualifying in November 2007.
Neither Spearman-Burn considers himself the favourite in the strong South Island amateur field of 112 male amateurs.
Peter: "I doubt it."
Thomas: "No, not really. It's a really strong field."
The twins both play off scratch handicaps out of the Miramar club, and have regularly played together as part of various Wellington teams.
Peter has had a touch more success, winning both the North Island and South Island amateurs last year, earning selection in the New Zealand team and twice qualifying for the New Zealand Open at The Hills.
But Thomas, younger by just two minutes, is - like his brother - a member of the New Zealand Academy, has also represented his country and won the Bledisloe Cup for leading amateur at the Open last year.
They were introduced to golf by their father, Mark, who has come south for the tournament with the twins' mother.
Brotherly love extends only so far when it comes to sport but the twins enjoy having each other on the course.
"It's actually really good motivation when you see your brother out there picking up birdies," Peter said.
Both intend to turn professional within the next year or two.
"Definitely.
"Time to make some money," Thomas said.
The Riordans both play off a plus-two handicap out of the Takaka club.
Sean Riordan, a member of the New Zealand Academy, said he and his brother were similar players.
"We're very competitive.
"He's probably stronger at putting and I think I'm a bit stronger mentally," the older brother said.
"That could just be a maturity thing."
It was brother on brother last year when Wellington played Tasman in the interprovincial tournament in Palmerston North.
Thomas Spearman-Burn beat Blair Riordan 3 and 2, and Peter Spearman-Burn beat Sean Riordan 2-up.
Others to look out for in the South Island tournament include New Zealand representatives Ryan Fox (Auckland), Andrew Stewart (Tauranga) and Ben Campbell (Masterton), and recent North Island champion Nick Gillespie.
Leading local hopes include the experienced Brent McEwan and the talented Duncan Croudis, who won the national under-19 title last year and nearly qualified for the New Zealand Open.
Runaway North Island amateur champion Lydia Ko - still just 12 - will be the player to watch in the women's field in the absence of national champion Cecilia Cho.
Zoe Brake (Whakatane), Emily Perry (Lochiel) and Caroline Bon (Northland) will be other challengers.
The top 60 men plus ties will play at the weekend, with the women's field of 30 cut to 15 for the final two rounds.