South Africa's Test captain Faf du Plessis is in a "race against time" to play the opening match against England at Lord's, which starts on July 6. Du Plessis is awaiting the arrival of his first child, who is expected in the first week of July, and with his wife Imari choosing a natural birth, there is no speeding up the due date.

Du Plessis, who will miss the T20 series in anticipation, is hopeful the baby will arrive in the next two weeks, though he left the door open to remaining home for longer if necessary. "I'm pretty nervous, to be honest. It's now just a countdown for when the baby comes," du Plessis said at the launch of CSA's Global T20 league on Monday. "My wife is pretty certain that she wants to go the normal route so that takes longer. It now becomes a race for the first Test match."

Du Plessis, who debuted in November 2012, has not played a Test at Lord's and admitted it was on his bucket-list. Seemingly, this would be his last chance to take part in one - he is already 32 and if South Africa only return to England in five years' time (the same length of time between their previous tour and this one) - it is unlikely he will still be playing.

If du Plessis is not able to make it back in time for the Test, South Africa will be without a captain and a senior batsman. While the spot in the line-up could be filled with the likes of Theunis de Bruyn, who played in Hamilton and is a regular No. 3, who leads the team will be more tricky.

AB de Villiers confirmed to ESPNcricinfo that he will not be persuaded to stay on for longer after opting out of the entire Test series to manage his workload. De Villiers will lead in the T20s and will then return home, to prioritise family time. His second child is also due in July.

That may mean Hashim Amla, who stepped down from the Test captaincy in January 2016, may be forced into an emergency substitution. Or South Africa may look to senior opener Dean Elgar or even JP Duminy, who has led in the T20s, for leadership.

This is the second England tour in which a South African captain has been an expectant father. In 2012, Graeme Smith returned home after the first Test at The Oval for the birth of his daughter and returned in time to play the second match at Headingley.