Somerville, 36, has already had one session with the Bay's "Frontrow Factory" squad which contains promising frontrowers from secondary school age up to those in the Magpies wider training group. He will visit the Bay once a fortnight during the ITM Cup season, attend the Magpies pre-season camp in Rotorua next month and complete regular video analysis sessions on the Magpies scrum.
"Basically my job is to help make the scrum better each week. If I can give the boys one or two pointers each week to tick off, I'm sure we will achieve our goals. As scrum coaches, we just guide these players ... for scrums and lineouts we facilitate drills and give advice but they have to own it," Somerville explained.
The former Onga Tiko player who played 115 Super Rugby matches for the Crusaders from 1999 to 2008 and 16 for the Melbourne Rebels in 2011 pointed out the Bay has a reputation for producing one or two props who are ready for Super Rugby each season. He is looking forward to helping his brother develop his coaching skills.
A father of three girls aged 8, 6 and 4, Somerville spent one season as a scrum doctor with the North Harbour ITM Cup squad. To avoid any conflicts of interest, the Magpies will be the only ITM Cup squad he works with this season.
Having progressed from the Napier Boys' High School 1st XV to the Onga Tiko Colts side while at Smedley Station during the 1996 and 1997 years before moving to Canterbury, Somerville said it would be easy for him to relate to many of the frontrowers he would be working with.
"I'm sure a lot of them will be wanting to follow a similar path to the one I took."
From 2008 to 2010, Somerville played 36 games for Gloucester in the Guinness Premiership. His playing career, which also included 56 first class games for Canterbury from 1998 to 2008, ended with the Rebels.
Somerville, who experienced one loss against England during his playing career - 15-13 at Wellington in 2003 - said he enjoyed the close first test which saw the All Blacks pip England 20-15 in Auckland last weekend.
"Some individual executions let the ABs down at times but I quite like a tight test ... it brings a bit more interest back into it."
He believed the All Blacks scrum had the upperhand for the first 60 minutes and the Poms scrum had the better of the final quarter.
With no changes to either frontrow for tonight's test in Dunedin, Somerville is predicting a 28-18 win to the ABs.