Paul Nation, the chairman of Karaka Rugby Football Club, said Mann was new to the club.
"He was a lovely boy and fitted in right away. He moved here because a lot of his friends play for the club. We are all devastated."
Richie Dowd, 22, who lives in the house where the car crashed, said he heard a loud thud and the power was suddenly cut.
Mann was believed to have died on impact.
The other three boys, all aged about 19, were taken to Middlemore Hospital with injuries including concussion, a broken arm and a broken leg.
Richie said: "It's not what you expect for a Friday night and it stops and makes you think. The whole thing was very shocking."
Danial Vincent, a stepson of Auckland councillor Callum Penrose, was in the front seat and suffered a broken arm.
Danial posted on Facebook: "Still cannot believe what happened, can't remember anything since like 12am. Thanks to everyone for the get well wishes. All mine are with big man Norman Mann. The most genuine guy I ever met, look after the boys up there man. If I could change the past I would in a heartbeat. I don't hold anything against u Norm. Ur one of my best mates I've ever had... Rest easy bro!!"
The boys in yesterday's crash were also friends with Liam Jackson, 18, Alan Jones, 18, and Ashley Foley, 19, who were killed when their car smashed into a tree on Gordonton Rd, 7km northwest of Hamilton, in July last year.