What's the best thing about being a national head coach?

"It's only temporary," was Adrian Birrell's snappy response.

He would know.

Birrell took charge of South Africa for the second Test against England at Trent Bridge, after Russell Domingo had to return home in tragic circumstances following the death of his mother. Like Dean Elgar, who stood in as captain for Faf du Plessis in the first Test, Birrell is quite keen to give the main job back. "Russell will be back for the next Test and I wasn't head coach, I was just acting head coach," Birrell said.

Jokes aside, Birrell actually knew exactly what to do. Not only has he been a head coach for longer than a week - he was in charge of Ireland for five years and oversaw their 2007 World Cup campaign - but he has been at Domingo's side for four years at this level and several more in the Eastern Cape. They understand each other's ways and so when Domingo had to go, Birrell could pick up from exactly where he left off. "It was business as usual. We prepared the same way as in all other Test matches - we just did exactly the same thing," he said.

It's difficult to believe the same preparation that preceded the limp display at Lord's produced the opposite result at Trent Bridge, but there are other factors to consider. While South Africa made fewer mistakes in the second Test than they did in the first, England made more, the little moments where luck was required went South Africa's way - Hashim Amla was out on 25 but England did not review - and they had their captain back. Birrell admitted du Plessis' return made a difference, more so because Domingo was not there. "This is his [Faf's] team. He is very much in charge and his leadership is very strong and very calm. He demands, but he demands in a very pleasant way, that players really perform for the team."

While du Plessis holds things together on the field, Domingo does that job off it. And the squad yearned for the steadiness Domingo's provides. "We all enjoy his calmness, he is very calm under pressure and he has been under a fair amount of pressure over the last few months. And his humour. We miss that," Birrell said.

From here on, that pressure will only increase. By the time Domingo rejoins the squad at the weekend, CSA's board will have heard from the five-man panel they appointed to recommend a candidate for the position of head coach. The board meets on Friday when the committee, which includes former national coaches Gary Kirsten and Eric Simons, reveal their choice.

The board does not need to agree with that choice. They don't even need to make a decision on whether they agree with it on Friday, but they may feel pressed to because Domingo's contract is up in three weeks and South Africa start their home season a month later so they will want to have a structure in place. Moreover, if there is to be a new coach and he is to come from within the system - and it is believed that will be the case because Lions' coach Geoffrey Toyana is the frontrunner for the job - then the board will need to give the franchise concerned enough time to find someone else, especially as their own pre-season plans get underway.

That means the end of the England series will be played with even more background activity than South Africa have already had, and they've had plenty. Apart from du Plessis' first-born, Domingo's family emergency they have also had to deal with Kagiso Rabada's suspension, the hangover from a disappointing white-ball campaign, the concerns after an even more disappointing A-team series and the noise about AB de Villiers' future. Now they will also have an atmosphere swirling with speculation over who will coach them going forward.

Though CSA has said they will only make an announcement after the last Test, they may be forced to do so sooner, especially if the board make a decision on Friday. Either CSA can reveal that decision immediately or they can ask the board to keep the decision quiet until August 9. But then they run the risk of the news coming out anyway.

Should the board want more time to decide there will still be scrutiny because the name of the person the panel recommends will be highly sought after. Should that name leave the boardroom, CSA may find themselves no longer in control of their own process.

One source told ESPNcricinfo that an alternative is being considered which will see the new coach announced before the final Test on August 4. That scenario is the worst of the lot. In the best case, the fourth Test will be a must-not-lose (if South Africa are leading 2-1 then a draw would be enough to secure the series) but there is every chance it will be a must-win. It may not be wise of CSA to add the tension of a new coach to the mix that week.

Whichever way things go, the search for a new coach is badly timed and maybe even unnecessary except to meet corporate governance requirements. Domingo has done reasonably well, especially last season, and has the full support of senior members of the squad. It seems bizarre that with everyone from de Villiers - who has indicated that his own future will depend on who the new coach is - to du Plessis to Elgar and Vernon Philander backing Domingo, CSA would want to look elsewhere but one reason may have been that Domingo wanted them to. Until a few days before the applications closed, Domingo had not decided whether he wanted to carry on but has since confirmed his reapplication and his interest in taking South Africa forward.

Whether CSA feels the same way may depend on if they think Domingo can win the 2019 World Cup - since that is the duration to which they next contract will run - and not necessarily on the outcome of the Tests, which could also send a confusing message to a team in the middle of a series. Given all that, it's worth wondering how South Africa will cope in the second half of the series.

But Birrell believes it will be by using the same methods as they have since January, when it was announced during the first ODI against Sri Lanka on January 28 that CSA start a search for a new coach: by blocking it all out.

"We speak a lot about not bringing outside influences into our inner circle. We work very hard at that. The media is noise and its kept on the outside so whatever you say doesn't affect us," he said with a dose of humour. "In the last I don't know how many months, there has been a lot of uncertainty but I don't think it has affected the players at all and it certainly hasn't affected the management. When we regroup, we will be boring and we will prepare in the same way we did earlier. We do pretty much the same stuff every time. It's not rocket science but it works."