Based on the Four Home Nations Championship, the Auckland version was conceived as a way to extend the club rugby season, serving a similar purpose to the village rugby played by Samoan, Fijian and Tongan players.
Now in its ninth year, the three-week competition will include 15-a-side and sevens rugby following its inclusion as an Olympic sport.
Although the tournament is a social affair, fierce patriotism always surfaces.
"It's the sort of rivalry where we belt each other for 80 minutes then you're all having a drink together afterwards," says Bernie.
"We just want to beat England," adds Derek, holding up a fist.
Recruiting Irishmen has always been relatively easy - it usually takes a shout-out at the local pub.
"It's very hard to get Welsh guys," says Derek. "Maybe it's because not as many people are coming out from Wales these days.
"But we're the most social side," he says of his team, which is yet to win a tournament.
"Oh, that's debatable," argues Bernie, whose team has a few Irish songs in their repertoire.
The teams wear replica jerseys and belt out their nation's anthem. The finals are always entertaining, featuring Irish dancing, Scottish bagpipes and a haggis ceremony.
"We like the idea of keeping it how rugby used to be," says Derek.
Beyond the game, Bernie and Derek say it's also a good tie to the countries' social clubs in Auckland, which are looking for more members.
"With our Welsh club, there's been a big drop in numbers, to the point we don't know whether we'll keep going or not. But the Welsh love rugby, it's a way of getting people together."
Bernie says the Irish Club would also welcome more members.
Grins the 48-year-old, who played 32 matches and two World Cups for the All Blacks from 1987 to 1991: "It's hard to recruit young guys like us."
KICK OFF
The 15s tournament is played on Saturdays from August 25 until September 8 at College Rifles Park, Haast St,
Remuera.
The Sevens tournament is played on Saturday, September 15 (Grammar Carlton Rugby Club, Puriri Drive, Cornwall Park) and Saturday, September 29 (Suburbs Rugby Club, Racecourse Parade, Avondale).
To find out how to get involved in the tournaments, contact Derek Lewis, ph 021 511 496, or see www.nzfournationsrfc.co.nz/n.z.-four-nations-rfc/.
If you're interested in joining the Friends of Wales Club, ph (09) 524 7767.
Past champions: Ireland (2004, 2005), England (2006), Ireland (2007), England (2008), Scotland (2009, 2010, 2011).
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