Uruguay did make the All Blacks work for it, particularly during a frenzied opening quarter during which somewhat bizarrely three tries in 16 minutes - two for New Zealand and one for Uruguay - were chalked off on review. But once McKenzie skipped in off the back of a scrum on the five-metre line, New Zealand proved irresistible. Richie Mo'unga was the next man in, again off the back of a close-range scrum, before McKenzie lit up the packed stadium by collecting his own chip on the touchline before keeping the ball in play with a one-handed pass to winger Will Jordan.
Scrum-half Cam Roigard secured the bonus point just before half-time. Maintaining the pace impressively after the break despite a flurry of substitutions, New Zealand ran in a further seven tries, with winger Leicester Fainga'anuku grabbing a second-half hat-trick. The All Blacks head to the knock-out stages with some serious momentum.
McKenzie, the Mastercard Player of the Match, said: "I think it was a really enjoyable game, pretty free-flowing. It took us a long while to break Uruguay, they defended us really well and then we were able to put some points on the board, so really proud of the win.
"We have got to where we want to be, we know we have to get better from this week and move on to the quarters whoever we play. We're really excited for what's to come."
About his eye-catching offload, he added: "I got pretty lucky to be honest, it bounced up to me and Will Jordan was on my inside to score the try. I'm glad that one bounced my way."
All Blacks captain Sam Cane paid tribute to second-row Sam Whitelock, who set a New Zealand record with his 150th cap, saying: "It's a phenomenal achievement, that's a lot of test matches. Anyone who has played a test match knows it's not just a game on the weekend, it's all the work that goes into it and he is someone who optimises professionalism and a lot of the work he puts in during the week is relentless. I think that is why he has been able to have such a long and successful career. He is a huge part of this team."
New Zealand head coach Ian Foster said of the All Blacks' performance: "Really proud of it. I thought Uruguay really honed in in that first 20, they showed a massive degree of spirit and managed to slow the game down. We expected that sort of game, we talked about how this was going to turn into a bit of a bun fight at the breakdown.
"We held our composure very well and were quite clinical. It was a little bit different from last week in that we had to grind our way through that contact area. It was hard to get quick ball but I'm pleased with the patience."
Uruguay captain Andrés Vilaseca said: "Today we were against the best team in the world and sometimes you just have to keep pushing and try your best. We can be very proud of ourselves.
"I think we had an amazing World Cup. Playing France, the host nation, Italy, Namibia - we won - and now New Zealand, playing the best team in the world. It's about learning and trying to give our best and trying to grow the sport in Uruguay. It has been amazing."
Los Teros head coach Esteban Meneses added: "I am very proud of the players and the staff. We came here to make history. New Zealand are the best team in the world. We played well in the first 20 minutes. They are a very tough team in the contact. I am very proud of Uruguay in the World Cup.
"I love the passion of the players. It's incredible. They play with their heart. They are very good players and very good people. I love them."