has taken credit for sparking the flame that lit up Kagiso Rabada
's performance in the Wanderers Test. While Elgar told the broadcasters he was "not going to get into" what had riled Rabada up in the immediate aftermath of the Test, he later revealed at the post-match press conference that it was him who confronted Rabada after the first Test, where he went wicketless on the opening day but finished with seven wickets.
"I went up to KG and I said to him, 'You are an immensely respected cricketer within our group and at the moment I don't think you are conducting yourself extremely well." Elgar said. "I know what KG is capable of. When KG's got his tail up, there's no better bowler than him and I have experienced quite a few guys who have been part of this team. It was a good chat. I can have those chats with KG and he responds extremely well. He takes it away, he lets it process and thinks about it overnight and then he comes back the next day with a scenario for me."
The conversation clearly had an impact on Rabada, who later went to Elgar and said he had considered the criticism leveled against him. "He was the one who came to me and said what we spoke about: I hit the nail on the head," Elgar said.
But what exactly was Elgar's issue with Rabada?
"He can sometimes be a little bit too relaxed and he needs to understand that his performance on the field and his performance in the change-room is huge," Elgar said.
On the third day of this Test, ESPNcricinfo published an analysis of Rabada's performances
over the course of his career and leading into the series. Specifically, it looked at how his performances have changed from when he was the best in the world in 2016 and 2017, and his inconsistencies since then. What the piece was unable to do was come to a conclusive reason for Rabada's performance, with reasons ranging from injury to being overbowled to the big money of the IPL.
It turns out that South Africa also don't know exactly what it is that happens when Rabada does not perform as expected, except that it occasionally happens to superstar bowlers.
"I think Eric Simons was talking about it in on air about getting a guy in a sweet spot to come out there and bowl," Mark Boucher, South Africa's coach told SuperSport. "There's certain guys - Dale Steyn was one of them - who at certain times in his career needed harsh words behind closed doors to bring the best out of him.
"KG - that spell he bowled, broke the game open for us. There was a bit of a spark in the dressing room, maybe it was what was needed in order to get him into that space. and we know when KG is like that it's difficult to get the ball away from him but also you want him on your side rather than the opposition team. There were fair words that were said and I think he's taken it on board and we're hoping we can get him into that sweet spot again for the next Test because it can only bode well for us."
Essentially, for Rabada to find his sweet spot, South Africa need something to happen that really irritates him. In this match, it was when Ajinkya Rahane was dropped by Aiden Markram and Keegan Petersen early on the third day, when neither of them reacted quickly enough to take the chance off the edge.
"I think that catch that happened off I think it was Rahane that landed between two guys. I think that also spurred him up a hell of a lot and you can almost sense that intensity on the field," Elgar said. "He was so focused and zoned in on his job at hand. And every time I asked him, do you want one more, he just said to me he is bowling now."
Rabada went on to take three wickets in 11 deliveries in a long morning spell, where he wouldn't let the ball go.
"KG has got that attitude, and he's got the want and he wants to bowl and he wants to contribute in a massive way. I mean, you have to utilise that as a captain. So it was awesome to see him fire," Elgar said.
Rabada is now the leading wicket-taker in the series, with 13 at 19.61, one ahead of Marco Jansen and two ahead of Lungi Ngidi and Mohammed Shami. He has assumed what Elgar believes is his rightful place at the top.
"I think he executed. He was understanding his value within the group."
Firdose Moonda is ESPNcricinfo's South Africa correspondent