Trent Boult has been ruled out of the second Test against South Africa in Wellington with the leg injury he sustained in Dunedin.

Boult did not bowl after tea on the fourth day of the opening Test - when he was one of just two frontline seamers alongside Neil Wagner - and even with the final day's play being washed out there has not been enough time for him to recover.

Tim Southee, who was left out in Dunedin to allow New Zealand to accommodate two spinners, will replace Boult although the final XI will not be named until the morning. A twin-spin attack would appear unlikely - the last time New Zealand did that at the Basin Reserve was in 2000 - which leaves Mitchell Santner vulnerable to either Colin de Grandhomnme, who would be a straight swap at No. 8, or Matt Henry who lengthen the tail.

"Injuries are part and parcel of cricket," Southee said. "He has had a big workload with five one-dayers and a big four days in the Test match in Dunedin. Trent being one of the fittest guys in the side does everything he possibly can to keep himself fit, so it's unfortunate that it has come but I am sure he will be right come Hamilton."

It is the second Test Boult has missed this season after he sat out the Hamilton match against Pakistan with a knee injury.

Boult's absence means New Zealand have lost two of their most experienced players with Ross Taylor having also been ruled out with his calf injury. Neil Broom will make his debut at No. 5. "There's still a couple of question marks over a couple of players," Southee said.

Faf du Plessis said: "He's a fantastic bowler and a huge loss for them. But anyone who plays international cricket is dangerous so I assume someone like Matt Henry [will come in] and Tim Southee didn't play the previous game is a high quality bowler. They've still got enough resources. This wicket won't take as much spin as the last one so I'm expecting they'll play one spinner."