North was injured in the final move of the game that saw Nathan Harris score the All Blacks' fifth try at Eden Park.
He is due to be assessed on Sunday but Wales have already called up Keelan Giles from the Wales Under-20s squad currently competing at the Junior World Cup in Manchester.
Giles, of the Ospreys, scored twice in the opening game of that tournament last week against Ireland and will link up immediately with the squad.
Head coach Warren Gatland has also sent for Cardiff Blues full-back Rhys Patchell, capped twice during the 2013 tour of Japan, following a blow to his regional club-mate Gareth Anscombe.
Gatland said: "We are going to assess George's hamstring tomorrow. Apart from that there isn't anything that looks serious."
Wales were left to reflect on pushing New Zealand close for more than an hour following tries by Taulupe Faletau and Rhys Webb that enabled them to lead 18-15 at half-time.
However, a powerful second-half display saw the reigning world champions extend their 63-year unbeaten record against Wales for another week at least.
Gatland said: "We will have learned a lot from that game and be better for it next week. It is the learning you take from playing against the best team in the world.
"We feel we get better the longer we are together. They get to experience a lot more games than us at that level of intensity and they are more familiar with it. We were blowing a bit and they just kept coming.
"There were a lot of positives to take out of that game. There were some lovely breaks. I said we had to be brave and be bold and we did that. We played some rugby. A couple of tries we scored were outstanding and we could have scored a couple more."
But Waisake Naholo scored in either half following Julian Savea's early try before captain Kieran Read and Harris crossed late on.
All Blacks head coach Steve Hansen said: "It wasn't perfect for large parts of the game but I'm pleased with how we kept our cool under pressure in a very good match.
"It was to be expected that we would be rusty in our first game since winning the World Cup and we have had massive changes.
"There are people out there who have answered a lot of big questions. And the biggest question they have answered was that they can react when put under pressure. They kept their self-belief, listened to the leaders and didn't get rattled."
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