"I've struggled the whole game, to be honest," he said after the day's play. "I feel like I've not been as consistent as I should be - if that makes sense - regarding line and length. Everything wasn't clicking."

That assessment applies to parts of the bowling in all three completed innings so far. In Pakistan's first, Kagiso Rabada was by far the most threatening of South Africa's attack but went wicketless, while Corbin Bosch admitted some of his wickets came off balls the batters didn't need to play at.

In South Africa's first innings, Pakistan were at times listless, and offered too many boundary balls to Aiden Markram initially, and Bosch later on. Then, in Pakistan's second innings, Rabada and Dane Paterson struggled for rhythm initially, and Bosch was off the mark before Temba Bavuma turned to Jansen to make something happen.

Jansen's fifth ball was short and wide, and Babar Azam, who had just got to his fifty, could not resist. He slashed it to deep point, where Bavuma had positioned Bosch, and Jansen received his first post-Christmas gift. Two overs later, Mohammad Rizwan got a short ball angling down leg and followed it with a half-hearted pull to be caught behind. In the over after that, Salman Agha drove leaden-footed at a full, wide ball. There are questions to be asked about all three batters' shot selections, but South Africa always expected them to choose those kinds of strokes.

"We know most of their batters like to play a positive brand of Test cricket. So we know that if we stick to our lines and lengths, they might leave one or two [balls], but their tendencies are they'll go at one," Jansen said. "We always knew that we're in the game, and we always knew that something's going to happen."

The most comical was yet to come when Saud Shakeel, on 84, was the recipient of a full toss that struck him on the pad, as he missed an attempted flick. Shakeel was hit under the knee roll, which says something about where Jansen planned for the ball to pitch before he got it a little wrong.

"I wanted to go for the yorker, but I probably missed it by a shin's length," Jansen said. "At the end of the day, people can say what they want. [But] he missed it, and it's a wicket. So I'm happy for that."

There was laughter all around when Jansen said that, which is a reflection of how entertaining this Test has been, although the quality of cricket has sometimes been questionable. Because both sides have provided some underwhelming cricket, it created a contest, albeit perhaps not an elite one. That was saved for the last 40 minutes, when Pakistan's seamers, while defending only 147, dished up spicy opening spells as the clouds gathered overhead to gawk on South Africa's increasingly knotted nerves.

Three of their top four were dismissed to the new ball being bowled on the right lengths, which was just short of a good length, even as the Pakistan quicks also took advantage of the extra bounce and nip on offer. Tony de Zorzi, Ryan Rickelton and Tristan Stubbs have all had their last say on this match, and South Africa could not be too unhappy with what happened to them.

"The three wickets they got were three good balls, so it's not like we threw our wickets away," Jansen said. "That's not to make it seem better. But as long as they get us out with good balls, there's only so much you can do as a batter. You can only play what you see - you can't pre-empt or pre-meditate what you want to do - because on this pitch, you're going to get yourself in trouble."

If Jansen ends up batting in the chase, that might mean South Africa are in some trouble, although they bat deep and he has a plan.

"My mental point of view is to be as disciplined as possible for as long as possible. We know that with the new ball, it moves quite sharply here - especially in the second innings of the game," he said. "Once the ball gets older, it gets a lot easier to bat, and it's a nice scoring ground. So with the new ball, [it is] definitely going to move sideways, and then the odd ball will shoot up and the odd ball will also keep low.

"From my perspective, if the ball shoots up, just get your hands out of the way, and then if the ball keeps a bit low, just stay nice and tight in terms of your bat next to your pad. Those two are the difficult ones to keep out. The balls that move sideways, we're used to that, so I think those are going to be the challenges for tomorrow."

Explained in those purely cricketing terms, it sounds as though South Africa have a good grasp of what is required of them. But there will be much more than just bat vs ball going on on Sunday. There is the expectation of securing this win to reach next year's World Test Championship final, and the pressure of being South African in a chase. You may think there is also some cushioning because South Africa only need to win one out of this and the next Test. But putting themselves in a must-win situation at Newlands will come with its own set of mind games.

South Africa will want to finish the job here, but for that, they will need the kind of steel that has not yet been on display at SuperSport Park. But with so much at stake, it may be time for something we've not seen so far.