However, that average drops to 21.90 at a strike rate of 61 opening 12 times against South Africa.
Guptill has been practising regularly since his last appearance; the opening Chappell-Hadlee ODI at Auckland.
"[The rehabilitation] was more about strengthening the hamstring and running at top speed," coach Mike Hesson said. "He has been keeping his skills up the whole time, but hasn't been in the middle. That's challenging, but he's a world-class player we're keen to have back."
Captain and No.3 Kane Williamson would be entitled to a discreet fist pump.
The latest he has entered the New Zealand innings in the last seven ODIs is the start of the fourth over.
Williamson has scored 321 runs at an average of 53.50 during that period, but consistent early entrances place him under undue pressure.
After two close games in Hamilton and Christchurch, the top order failure in Wellington saw Williamson and Ross Taylor at the wicket by the end of the third over.
Their subsequent failures saw New Zealand stumble to 112, their lowest total at home since being dismissed for 73 by Sri Lanka in January 2007.
The innings was their worst ODI score against South Africa (previously 134 at Cape Town in December 1994) and trumped the biggest margin of defeat between the sides (143 runs at Auckland in March 1999).
Levelling and then winning the series looks daunting against the world No 1s, but Hesson insists they have options.
Guptill's recovery will require a rejig of the top order. Tom Latham seems a candidate for a spell with 35 runs from his last seven ODI innings, but that is complicated by tidy work as the incumbent wicketkeeper and the fact he topped the New Zealand averages as a specialist batsman during the ODI tour of India in October with 244 runs at 61.
Alternatively, Dean Brownlie could retain his place on the back of 130 runs at 32.50 from his last four ODIs.
Hesson confirmed Luke Ronchi was the likely gloveman for Hamilton, despite collecting 47 runs from his last five ODI innings.
"We talked at the start of the series about giving both keepers an opportunity," Hesson said. "Tom's had the first three, Luke's likely to get a go.
"There's no doubt Tom's struggled, but he's come off a series in India where he was our best player."
Williamson added: "Tom works hard like all of us to get more runs, and he's been unlucky finding fielders with some dismissals against a good attack."
Another selection option might be to elevate Ronchi to No 5 and replace Neil Broom, who has returned 2, 2 and 0 this series after stellar displays against Bangladesh and Australia.