Minto was felled in that seventh round by Parker, the second time legitimately with 25 seconds remaining when he caught him with a right hand to the head.
Earlier Parker had pushed him to the floor, an act which earned a warning from referee Brad Vocale. However, the American was in no doubt as to who had the upper hand in the fight, saying afterwards he refused to get hurt for the sake of it.
Parker showed a powerful jab, in particular, as he fought against the smaller Minto at the Vodafone Events Centre in Manukau. This was a world away from his brawling victory over Afa Tatupu, the last time he fought in New Zealand. This time he was precise, disciplined, and very fast. Importantly, he remained cut free after cutting badly above his left eye against Tatupu.
"I said I was lean and mean, and you saw that," Parker said afterwards.
"I executed the plan we put in place. It's a good victory for us tonight."
Trainer Kevin Barry said: "The public of New Zealand saw a much more mature fighter than the one they saw 12 months ago. They've got a fighter then can be very proud of."
Minto, who admitted to fighting with a broken nose, an injury he denied during the week, said: "He's a big, strong heavyweight. He has the skill and the power. I was very impressed.
"I didn't want to get hurt, I've got two beautiful kids and a wife to go home to."
Parker's power and speed was evident from the start. He took control of the first three rounds before Minto began to make inroads in the fourth.
A big right hand in the fifth round with 12 seconds to go put Minto down and he must have known then that he was fighting a losing battle.
The sixth was more even, both unloading on each other, before Parker took control for the final time in the seventh.
The victory improved the 22-year-old's record to nine victories with eight knockouts, but it was the manner in which it was achieved which will impress his camp and promoters Duco. His dream of a world title fight remains alive.
Earlier, Robert Berridge continued his rise with a stunning first-round knockout victory over Brazilian Rogerio Damasco.
The win will have helped Berridge, the highest-ranked professional fighter in New Zealand at the moment, get closer to a world title fight against undefeated Russian and WBO champion Sergey Kovalev.
It improved his record to 24 wins, 20 by knockout, with one loss and one draw, and it was as brutal as it was short.
The southpaw Berridge, nicknamed The Butcher, knocked Damasco down with 1min 22secs remaining in the first round, and charged forward again to again knock the Brazilian down only seconds later. Damasco claimed to be fine, but his corner threw the towel in.
- Patrick McKendry of APNZ
