New Zealand have fought back well in the first cricket Test against South Africa but have lost senior batsman Ross Taylor to what appears to be a serious injury.
Taylor limped off Dunedin's University Oval on Thursday afternoon with a calf tear.
He was on eight when he pulled up after running between wickets, but medical staff weren't immediately able to say how bad it was and if he might be able to bat again in the match.
At stumps on day two, the hosts were 177-3, 131 runs behind South Africa's first innings of 308.
Kane Williamson was 78 not out and night watchman Jeetan Patel nine.
"It's a shame to see him limp off like that - he's a big player for us," Kiwi bowler Trent Boult said after play.
"The way he walked off it doesn't look too good."
However, he believed the match against the higher-ranked South Africans was nicely balanced.
"I think we got a lot of reward for keeping it simple yesterday and not letting them get too far ahead in the game and picked up six tidy wickets this morning."
Williamson showed his class against the South African attack. Three of his 11 fours came in one Kasigo Rabada over to bring up his 26th Test fifty.
However, three times he had outside edges fall short of first slip and not long before stumps he survived a tight run out chance when Henry Nicholls sent him back from attempting a third run.
Earlier Williamson and Jeet Raval (52) set a New Zealand second-wicket partnership record of 102 against South Africa, beating the previous best of 90 by Matt Horne and Nathan Astle in February 1999 in Auckland.
They scored at a good rate of more than 3.5 an over before Raval's third Test fifty came to an end when he needlessly clipped spinner Keshrav Maharaj to Dean Elgar at midwicket.
Nicholls (12) went not long before the close of play, brilliantly caught at first slip by a quick-reacting Hashim Amla.
In the sixth over of the New Zealand innings, paceman Vernon Philander's his first ball from around the wicket to Tom Latham took the outside edge and the opener was gone for 10.
Philander returned figures of 1-37, Maharaj 2-57, Morne Morkel 0-26 and Rabada, who picked up food poisoning on Wednesday afternoon but is believed to be recovering, 0-46.
South African bowling coach Charl Langeveldt believed the Kiwis had had the best of the wicket so far and were reaping the reward of working hard.
He also lamented not being able to contain the quick scoring of Williamson and Raval.
"In hindsight we went for too many fours," he said.
"Kane put us under pressure, especially against the spinners. He didn't let the spinners settle down.
"Locking up one end would have been ideal but at the end Kane, he was on fire."
South Africa won the toss and opted to bat on the first day. Opener Dean Elgar top scored with 140 and there were also contributions from Temba Bavuma (64) and Faf du Plessis (52).
For New Zealand Trent Boult took 4-64, Neil Wagner 3-88, Patel 2-85, Jimmy Neesham 1-34 and Mitchell Santner 0-32.
