Wales slumped to their heaviest defeat to New Zealand in 13 years as Beauden Barrett inspired the All Blacks to a 46-6 victory in the third Test in Dunedin.

Fly-half Barrett scored 26 points, including two second-half tries, as the world champions swept aside the tired tourists to secure a 3-0 series whitewash.

Dan Biggar kicked two penalties to give Wales an early lead at the Forsyth Barr Stadium, but it was all New Zealand thereafter as they blitzed the visitors with six tries.

Ben Smith and George Moala scored in the first half before Dane Coles, Barrett twice and Israel Dagg in stoppage time completed the rout.

The All Blacks showed five changes, including a debut for Highlanders flanker Elliot Dixon at his home stadium.

Biggar twice kicked Wales ahead in the opening quarter with penalties, the first inside three minutes and the second just seconds after Barrett briefly levelled.

Barrett controlled the hosts' play but Smith proved the danger. The pair combined for a counter-attack but Smith was held up by Rhys Patchell.

Kieran Read attacked from the resulting scrum before scrum-half Aaron Smith, winning his 50th cap, switched direction to Ben Smith on the right wing. He rode the tackle of Hallam Amos to touch down for the opening try on 23 minutes.

Barrett missed the conversion but swiftly kicked a penalty for an 11-6 lead.

Wales' kicking game continued to hand the All Blacks plenty of possession and new centre Moala went close to a second.

Dagg and Ben Smith burst clear but Moala was ruled to have lost the ball under the challenge of Liam Williams, who was injured in the process.

Wales thought they had cleared the danger only for Dagg to mount another swift attack as he brushed past opposite number Patchell with ease.

Brodie Retallick, Julian Savea and Aaron Smith kept the move going and Moala picked up and drove over from close range for the second try on 33 minutes.

Barrett converted for an 18-6 lead that they held until half-time despite a strong Wales surge just before the break.

Luke Charteris, Sam Warburton and Jamie Roberts all went close but, unlike in the final stages in Wellington last week, Wales could not find the scoring pass.

New Zealand began the second half at the same blistering speed, while Welsh errors meant they struggled to clear the danger.

A forward pass by Jonathan Davies behind his own try line handed New Zealand an attacking scrum and Barrett crashed through for a try that he converted himself.

Wales were given a glimmer of light when New Zealand were reduced to 14 men after Sam Cane was shown a yellow card early in the second half.

But Wales could not capitalise and the All Blacks struck next just moments after Cane returned.

Barrett, now playing at full-back, raced onto Lima Sopoaga's long pass to beat Amos and Biggar to his second try.

Hooker Coles burst through for the All Blacks' fifth try on 62 minutes but Sopoaga saw his effort ruled out for failing to ground the ball after Welsh replacement Ellis Jenkins spilled a lose-ball.

Wales kept searching for a try but were caught in the third minute of stoppage time when Dagg raced upfield to complete a big win.