South Africa will “go back to old-fashioned Test cricket” as they look to take five wickets to complete a win on the final day at St George’s Park. This, after they “went searching” in the last 90 minutes of the fourth afternoon.

A slightly frustrated Keshav Maharaj, who was the last to strike in the 34th over – before Kusal Mendis and Dhananjaya de Silva batted out 18.5 overs more – said tighter disciplines will be key with the old ball on a surface that remains relatively good for batting with Sri Lanka 143 runs away from levelling the series.

“It requires a lot of patience, especially as the ball gets older and softer. The wicket becomes a little bit more placid but we did go searching a little bit, if I’m honest,” Maharaj said at the post-play press conference. “Hopefully tomorrow we’ll go back to old-fashioned Test cricket like we did in that period where we got those seven wickets in the morning.”

Maharaj was reflecting on the third day’s play where South Africa forced a Sri Lankan collapse of 7 for 67 to take a 30-run first innings lead. Then, Marco Jansen extracted good bounce and Dane Paterson bowled an excellent and accurate spell where he found late movement with the second new ball. This time, South Africa will have to wait 28 overs more before the second new ball is due and they will have to apply their disciplines for longer, especially against batters who are set.

The partnership between Kusal and Dhanajaya has grown to 83, with each on 39 not out. While their growing ease at the crease may be causing some concern, South Africa know they are essentially a wicket away from the tail and if they get there, the rest could unravel. “Traditionally, the wickets do happen in clusters. There can be a period where the game goes nowhere and then all of a sudden, it takes one wicket to basically be the catalyst,” Maharaj said. “It’s about staying patient and hopefully reaping the rewards of some hard graft tomorrow morning.”

South Africa have already had two lessons in patience – the one when Sri Lanka were 242 for 3 overnight and then finished on 328 all out on day three and the other on the fourth day. Sri Lanka looked comfortable on 117 for 3, with a partnership between Angelo Mathews and Kamindu Mendis that sat at 53, when Maharaj made an important double-strike. He removed Mathews and then Kamindu in successive overs and bowled to a plan that worked.

With Mathews, South Africa wanted to “encourage a shot” because they believed they had enough runs on the board for Maharaj gave it extra flight, and Mathews tried to hit him over midwicket and was bowled. “It was a big wicket. It obviously led to the wicket of Kamindu a couple of overs later.”

Once Mathews was removed, South Africa tried something different against Kamindu. “It didn’t look like he wanted me to settle in the rough, so [I thought] let me come around the wicket and keep him in the crease,” Maharaj said. “And it just paid off quickly. It paid off with the first ball I tried that.”

Kamindu edged as he tried to work a delivery that spun into him into the leg side and Kyle Verreynne took an instinctive one-handed catch. Maharaj pointed to Bavuma in celebration, an acknowledgment of how their homework was earning them full marks.

At that stage, South Africa had Sri Lanka 122 for 5 and could probably sniff a win. They tried a few things because they felt they had “kind of earned the right a little bit to go searching, but probably not for as long as we did”, as Maharaj put it. Maharaj operated from his end until the last over of the session and continued to experiment with his lengths as he tried to find another breakthrough. At the other end, South Africa rotated through the seamers and though Kagiso Rabada and Paterson both found some movement, Sri Lanka balanced caution with enterprise and saw out the day.

In 2019, on this ground, Sri Lanka were 60 for 2 overnight on the second day, chasing 197. They got there without losing another wicket and Kusal Mendis was one of the batters that spearheaded that win. South Africa know the importance of removing him but understand that the best chance of doing that is to make sure their disciplines are strong and they don’t get too far ahead of themselves, knowing that a win would tick another box on their quest to reach the World Test Championship final.

“We acknowledge the bigger picture for everything, but it’s about a process. The boys are very comfortable just focusing on the now and not the future,” Maharaj said.

South Africa will be guaranteed a place in the final if they win this and their next two matches, and could still get there with fewer than three wins but then they will be dependent on other results.

Firdose Moonda is ESPNcricinfo’s correspondent for South Africa and women’s cricket