The 25-year-old was called into the side after youngster Luke Jacobson was ruled out of contention as a result of delayed concussion symptoms.
Jacobson has been battling with concussion issues throughout this year, and has sustained three in as many months.
Symptoms of those head knocks became evident in the All Blacks’ first two trainings of the week in Japan, with two-test rookie describing how he felt dizzy and light-headed as the 31-man squad practised in searing conditions in Kashiwa.
Consequently, he will be sent home once he feels ready to travel, with his long-term career at the forefront of the minds of Jacobson, Hansen and team doctor Tony Page when they made the decision to omit the 22-year-old from the squad.
With Jacobson set to be out of action for at least three months, a window has opened for Frizell to come back into the national set-up after being culled from the enlarged 39-man Rugby Championship squad last month.
The Tongan-born star was one of five players dropped for the Bledisloe Cup series following the All Blacks’ 16-all draw with South Africa in Wellington in July, and has since been plying his trade for Tasman in the Mitre 10 Cup.
He has been in good form for the rampant Mako, who sit unbeaten at the top of the Premiership table, and has been rewarded with an All Blacks re-call ahead of provincial teammate Liam Squire and injured duo Vaea Fifita and Dalton Papalii.
“I’m happy and excited,” Frizell said. “I was surprised to get the call.
“I called my mum straight away. I just said ‘I’m going to Japan today’ and she was just screaming.”
The five-test Highlanders blindside flanker, who can also cover No. 8 and lock, said he felt sorry for Jacobson, but couldn’t wait to be part of the World Cup journey that lies ahead.
“I’m gutted for him, [but] he’ll come back fitter and stronger. At the same time, I’m grateful for the opportunity.”
Hansen said it was an exciting chance for Frizell to prove his worth on the global stage.
“I can only imagine he’ll be ecstatic,” said Hansen.
“While it’s tough for Luke, its an opportunity for Shannon – so let’s hope he takes it with both hands.”
The All Blacks kick-off their World Cup campaign in a week’s time, as they take on the Springboks in Yokohama on September 21.
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