Ross Taylor's right calf strain on the second day of the first test between New Zealand and South Africa places additional pressure on the batting capabilities of Kane Williamson, certainly for this match and possibly for the series.
Taylor suffered the misfortune in the 43rd over with New Zealand 148 for two. He needed assistance to hobble off, and was set to be monitored overnight before undergoing a scan today.
Williamson was at the zenith of his defensive game, and needed to be on his way to 78 not out from 146 balls.
Vern Philander was landing the ball on a good length, seam up, and asking more questions than a White House journalist.
Supplementary probes were raised by Morne Morkel (in his first test since January 2016), Kagiso Rabada (suffering the remnants of food poisoning) and Keshav Maharaj (who drew the skipper into a couple of false shots).
However, the New Zealand captain appeared to employ a GPS on his off stump before expanding his stroke repertoire across the afternoon.
His performance was a blueprint for test batting after coming to the wicket at 15 for one in the 6th over with Tom Latham's exit.
"We have to play smart to contain Kane," South African bowling coach Charl Langeveldt said. "He put us under pressure, especially against the spinners... and even the seam bowlers.
"Locking up one end would have been ideal but, in the end, Kane was on fire."
At one stage Williamson was 10 off 48 balls as he soaked up pressure and allowed the shine on the ball to dull as it whizzed outside his eyeline. He received able support from Jeet Raval who made 52 from 102 deliveries before chipping a Maharaj delivery to Dean Elgar at mid-wicket.
The pair produced the highest second-wicket partnership for New Zealand against South Africa, overtaking Matt Horne and Nathan Astle's 90 at Eden Park in February 1999.
Langeveldt was concerned his quick trio would struggle to bowl at their capacity on the pitch.
"It hasn't gone a lot to first or second slip, so I think we've got our work cut out."
Williamson is familiar with success against South Africa after he came of age as a batsman with 102 not out to draw the test at the Basin Reserve on their previous tour in 2012.
More of that application will be required today to get New Zealand into a first innings lead and enable their spinners to bloom if they are to win a fifth test in 43 attempts against the Proteas.
The forecast suggests rain is on the way for the weekend, so time will play a key role if either side is to triumph.