His defensive work rate was phenomenal and he busted the advantage line with ease on the carry.
As expected, Magpies head coach Craig Philpott was delighted after the final whistle.
"That's awesome and that's shield rugby," he said.
Before the match Philpott said it would be decided by the team who controlled the ball the best and he agreed his troops did it well during the final minutes.
"But at the same time we gave them a couple of sniffs," he said referring to a penalty and a lineout which fortunately for the hosts resulted in a crooked throw from the Premiership Auckland outfit before the final whistle.
Philpott had every right to be impressed with the improved defence from the Magpies. They missed two tackles in the first half and none in the second.
His lengthy injury list took some of the gloss off the Magpies 11th successful defence in their latest tenure. All Black fullback Israel Dagg is out for the remainder of the season with a dislocated shoulder while prop Brendon Edmonds and centre Richard Buckman are expected to have numerous physio visits between now and Wednesday night's away match against Wellington.
The Magpies made a poor start conceding an early turnover and a penalty in front of the posts in the first minute, which Auckland pivot Simon Hickey converted into three points. The hosts equalised in the eighth minute when West succeeded with a penalty from 32m out after Auckland winger Ben Lam was penalised for a dangerous tackle on Buckman.
Auckland took a 6-3 lead in the 22nd minute when Hickey succeeded with another penalty after a scrum infringement 44m out.
Hickey slotted his third penalty five minutes later after a Magpie was penalised for coming in from the side at a breakdown.
The Magpies remained in the hunt when captain and No8 Brendon O'Connor crashed over for a try after some strong phase play from the forwards and West slotted the conversion to put the hosts ahead.
However, another conceded penalty after the halftime hooter gifted Hickey his fourth consecutive penalty and Auckland led 12-10 at halftime.
Poor discipline proved costly for the Magpies during the first half. They conceded six penalties, three more than the visitors.
Like the first half the second half was a real arm wrestle. Hickey missed penalty attempts in the 55th and 57th minutes from 58 and 39 metres respectively.
After another purple patch from the Magpies forwards West put the Magpies ahead with his solo try, which he converted.
This was the Magpies first win against Auckland since 2009. It has guaranteed the Magpies a semifinal and the challenge now for Philpott and co is to secure a home semifinal which will be done if they win against Wellington.
The Magpies final shield defence of the season will be against Waikato on October 9.
Match highlights
•Heartstopper: Magpies halfback Chris Eaton's 49th-minute knock on when the hosts were building momentum and close to the Auckland 22. A crucial turnover. Eaton was having a top game until then.
•Turning point: Bay of Plenty referee Nick Briant's final whistle. This nailbiter was in the balance until then.
•Player of the match: Magpies lock Mark Abbott. A huge defensive game and powerful on the carry.
•Scorers: Hawke's Bay Magpies 17 (Brendon O'Connor, Ihaia West tries; West pen, 2 cons) Auckland 12 (Simon Hickey 4 pens). HT: 10-12.
