Green Island squandered an early advantage to succumb to a more disciplined Taieri side at Peter Johnstone Park.
Green Island ran rampant in the first quarter, running in two tries and looking to dominate.
But when pressure was applied, mistakes crept in and cracks began to show.
This was particularly noticeable in the Island backline, with handling errors and players becoming isolated. Discipline was a factor, also, with the visiting side losing a player in each half to the sin bin.
This contributed to Taieri getting back into the game. Its forwards gained ascendancy and its backline was dangerous and error-free.
Two Andrew Reid penalties and a try to flanker Willis Scott had the undefeated Eels back in the hunt and trailing just 17-11 at the break.
Taieri took full control in the third quarter with tries to Michael Collins, Rhys Collins and Ben Nowell, but could not extend the advantage in the final quarter, despite Green Island playing with 14 men for the final 10min.
Taieri will take a lot away from this derby match, with its loose forward trio and backline excelling in the heavy underfoot conditions. Will Hurst, Aki Seuilli and Karl Bloxham also stood out in a well-drilled tight five.
Taieri 30 (Willis Scott, Michael Collins, Rhys Collins, Ben Nowell tries; Andrew Reid 2 pen; Nowell 2 con), Green Island 17 (Mika Mafi, Sam Eriepa tries; Joe Bartlett 2 con, pen). Halftime: Green Island 17-11.
