Blues sign former nightclub bouncer Karl Tu'inukuafe

Karl Tu'inukuafe shows his emotion during the national anthem before the Test between the New Zealand All Blacks and France at Eden Park on June 9, 2018 in Auckland. Photo by Phil Walter/Getty Images

Having gone from part-time nightclub bouncer to an All Blacks jersey in a few months, prop Karl Tu'inukuafe knows a good deal more about life outside rugby than the young talents who typically travel New Zealand's elite pathways to the big-time.

And that life experience was just one of qualities that proved attractive to Tana Umaga's Blues, who announced on Thursday that they had snapped up the 25-year-old on a three-year deal.

The Blues beat the Highlanders to the signature of a player regarded as one of New Zealand's most promising loosehead props, who made his international debut against France during the June Tests.

But only months ago he was barely known to anyone outside of Auckland, where he played for provincial side North Harbour and supplemented his income by working for a security firm.

Waikato Super Rugby franchise the Chiefs selected him after injuries gutted their front-row stocks, and Tu'inukuafe was so impressive that All Blacks coach Steve Hansen came calling.

Umaga, desperate to turn around the ailing Blues, hopes Tu'inukuafe can prove similarly inspiring in a Blues jumper.

"[Umaga] was just talking [to me] about experiences, I guess," Tu'inukuafe said on Thursday.

"There are a lot of young guys in the team, some of them probably haven't had as much life experience as others, like myself.

"I didn't really turn professional until I was 23. I guess I was living life outside of rugby before, so maybe I bring a different type of experience."

Joining the Blues means a return home to Auckland, his birthplace and the home of his wife's family.

He will also be reunited with his North Harbour coach and close mentor, Tom Coventry, who has been appointed the Blues' forwards coach next season.

Coventry was instrumental in turning around Tu'inukuafe's fortunes after the prop's weight ballooned to 170kg in 2014, prompting stern warnings from doctors.

"The turning point was definitely my health issues," Tu'inukuafe said.

"The doctor said to lose weight. Pretty much the easiest thing I could think of was playing rugby with my brothers and my cousins; that's why I decided to get back [to the game]."

The Blues contract means he is unlikely to need to stand doors again.

"Definitely, if someone came up to me this time last year and said next year you will be an All Black, I would definitely not have believed them," Tu'inukuafe said.

"[I was] standing at doors, security."

"I loved my job then but I guess now I can provide for my family and be in a healthier state than I was, so pretty happy about it."