In the final Test for both Hansen and Wales counterpart Warren Gatland, both sides showed intend on the pitch, but New Zealand were unstoppable as they outscored the Welsh by six tries to two.
The first came quickly, as lock Brodie Retallick produced a brilliant backhanded pass to Joe Moody, allowing the prop to bound in from 20 metres for a great front rower's try.
Richie Mo'unga converted and added a second after Beauden Barrett scampered over.
A sustained period of Welsh pressure followed – and paid off after a long miss-pass from Rhys Patchell found Hallam Amos, who shot over for a try.
New Zealand then roared back through veteran Ben Smith, before Smith got his double on the stroke of half-time, the conversion leaving the All Blacks in complete control at 28-10.
The three-time world champions carried the momentum into the second period, with Ryan Crotty finishing off an early surge.
Wales winger Josh Adams scored his seventh try of the tournament to usurp Shane Williams' Welsh record at a World Cup.
But Mo'unga then stepped through a poor tackle by Dan Biggar for a late try, taking his personal tally to 15 points as the All Blacks secured their consolation prize.
Steve Hansen paid tribute to New Zealand supporters on the @AllBlacks twitter feed.
A special message from Steve Hansen to all the All Blacks supporters around the world.#BACKBLACK pic.twitter.com/Gs3ROXfFvq
All Blacks (@AllBlacks) October 18, 2019
His incredible coaching record includes just 10 defeats in 107 Tests in charge.
Under Gatland, Wales have won 85 of their 151 Tests – but have lost all 12 against his native New Zealand.
Broadcast blunder
In the lead up to the match, All Blacks supporters back home were left stunned as the public broadcaster revealed it wouldn't be showing Hansen's and skipper Kieran Read's swansong match.
TVNZ said it would be airing Coronation Street instead, saying "it's not our choice".
"TVNZ was given rights to cover 12 matches and unfortunately the bronze game wasn't one," a spokeswoman said.
