One out, two in. That was South Africa's response to losing Dale Steyn to injury in the first Test against India in Cape Town. They already had Chris Morris and Andile Phehlukwayo in their squad, but Steyn's plight was a reminder of the Proteas' biggest challenge in their most exciting summer for some time. Duanne Olivier and Lungi Ngidi were both called into the squad for Centurion.

"I've got an eye on the future, because there is a lot of Test cricket coming up," captain Faf du Plessis explained on Friday (January 12). "As I have said very often, the success of our Test team is highly dependent on the fast bowlers we have in our armory. That's why Lungi has been brought into the squad - we want to get a closer look at him and what he can do. Before yesterday, I hadn't seen him bowl at all. I believe there is a lot of talent there. It's important for the next few months to have six or seven bowlers."

With two Tests to come against India in January, four against Australia in March, and no fewer than nine limited overs matches in February, South Africa have a jampacked schedule. But having taken on a new mindset to team selection, they are also likely to pick more fast bowlers in each game. Coach Ottis Gibson confirmed after the 72-run win at Newlands that under his watch, South Africa will take every opportunity they have to play four fast bowlers.

Hence the decision to pick Ngidi as well as Olivier. Ironically, despite the fact that Olivier has played five Tests, it is the uncapped fast bowler who is being touted for a game at Centurion. Morris is expected to get in ahead of both of them, but it says something about the excitement around Ngidi's potential that he has not been ruled out of the equation.

Although the 21-year-old burst onto the international scene last January with a fine Twenty20 international debut against Sri Lanka, 2017 was a frustrating year. More opportunities would have followed in England but a stress fracture kept him out. He has subsequently spent time on his strength and conditioning and it has shown - in his last first-class match he took 9 for 83 to bowl the Titans to victory over the Lions on a spicy Wanderers pitch. Little wonder that Gibson and du Plessis were watching Ngidi carefully in South Africa's training session on Thursday.



"He bowls a heavy ball," suggested du Plessis. "We're excited to have him in the group. I think there is a bright future ahead for him so I want to start that journey off with him."

Du Plessis reiterated a refrain from the tour of England last year, that Morris is suitable as part of a four-man pace attack, but is too inconsistent to slot into a three-man unit. With South Africa almost certain to pick four at Centurion, that should not be a problem, with Morris's pace and "X-factor" seen as an attribute.

"To have pace anywhere in the world is an advantage. If you don't have pace, your attack can get one-dimensional. I feel our attack has a lot of variety, so there is a huge X-factor to it," said du Plessis.

"If the pitch has variable bounce and fuller balls are coming past your head and shorter balls are staying down, then pace becomes more dangerous because you're thinking in the back of your head, 'I'm not sure what the pitch is doing.' Hopefully we can see that on this wicket towards the end of the Test match."

Keeping that variety will be the challenge as the demanding summer rolls on. It was not so long ago that Morne Morkel, Vernon Philander, Steyn and Morris were all out injured. Gibson is in the process of putting a high performance system in place for the fast bowlers to monitor the top players but also track the younger ones. It will take a little time to get up and running, but in the meantime at least du Plessis feels his existing charges are more dependable.

At the end of the tour of England, Vernon Philander's fitness needed to be discussed after the seamer pulled up on the morning of the fourth Test with a back problem. It took him four months to recover. Now that he is back, du Plessis sees a difference and he has mentioned it to Philander.

"The conversation was, 'Well done, the stuff you have been doing over the off-season is paying off. You're looking good.' At the end of the day it's about trying to get the best out of players. Vernon is in a good place where he is fitter. The most pleasing thing for me was to see that he was wanting the ball all the time. He wasn't tired after four overs, he was ready to go. If we cam have Vernon like that, it makes our bowling even more dangerous. I'm really pleased with the way he stepped up."