Dave Rennie has acknowledged South Africa as the standard-bearer heading into next year's World Cup, even as he expressed confidence in New Zealand's development after a 3-1 series defeat to the Springboks.

The All Blacks won the opening Test before losing the next three, with the Springboks sealing the series 43-28 in the final match played in the United States on Saturday.

"We'll wake up tomorrow and know we're moving in the right direction. We scored 17 tries in the four Tests. We're in a good place, but tonight will hurt," Rennie said post-match.

Rennie pointed to the statistical closeness of all four contests while conceding the Springboks made their chances count. "Look at all the numbers, and they're very even, but the Springboks were electric with their opportunities." He also noted that South Africa had grown stronger as the series progressed: "They've got better and better as the tour has gone on."

On the benchmark South Africa now set, Rennie was direct. "They're where we want to get to. We've been together for 10 or 11 weeks while they have a lot of experience." He did, however, raise the question of squad continuity on the South African side: "I'm not sure if all of those guys will still be here this time next year" — a nod to the age profile of the current Springbok group.

New Zealand face Scotland, Wales, and England in the November Nations Championship before opening their World Cup campaign against Chile in Perth on 2 October next year.