The weigh-in, held in front of a big gathering at a downtown bar, belonged to crowd favourite Parker. He flexed his muscles while on the scales and his height and size advantage looks significant.
Asked by the Herald how he would make that count from the first bell, he said: "I'm going to punish him from the outside, I'm going to pierce his face with my jab, that's what I'm going to do from the outside."
His 112kg was "muscle, pure muscle", he said.
Ruiz Jr told the Herald of his weight: "I'm really happy with that. We thought we were going to be 114kg, but we've been eating right and I've been taking care of myself. I'm going to come out strong."
Asked about how Parker's power ranked alongside that of his previous 29 professional opponents, Ruiz Jr said: "Everyone who is 200-plus [pounds] has a lot of power. It's a matter of when they hit you and where they hit you, that's what counts. I'm pretty sure he hits hard and I know I hit hard."
Main Event: Joseph Parker (Auckland, NZ) 111.9kg v Andy Ruiz Jr (Mexico) 116kg
Main undercard fight: Jeff Horn (Aust) 66.5kg v Ali Funeka (South Africa) 66.4kg
Julian Aristule (Argentina) 54.8kg v Isaac Dogboe (Ghana) 54.8kg
Laura Griffa (Argentina) 55kg v Shannon O'Connell (Aust) 55kg
Pablo Magrini (Argentina) 95.5kg v Junior Fa (Auckland, NZ) 122.5kg
Ash McConnville (Christchurch, NZ) 82.3kg v John Parker (Auckland, NZ) 86kg
Che Barlow 105.6kg v Dave 'Brown Buttabean' Letele (Auckland, NZ) 127.5kg
Watch the weigh-in: