The Proteas have been struggling in T20 cricket and have lost their last five series in that format, which should raise concerns as preparations for this year's World Cup in India.
One of the areas where supporters should be encouraged, though, is in the depth that head coach Mark Boucher has at his disposal in the top order.
In the recently completed series against Pakistan, which South Africa lost 3-1 at home, the hosts were without all of Quinton de Kock, David Miller and Du Plessis, who had left to take part in the ongoing IPL.
Captain Temba Bavuma, too, was ruled out with injury.
But, in their absences, the Proteas fielded a new opening pair in the form of Janneman Malan and Aiden Markram that more than looked the part.
Markram scored 179 runs in the series and Malan 127 to be their country's best performers in that department, while Rassie van der Dussen and stand-in skipper Heinrich Klaasen also gave good accounts of themselves.
All of a sudden, when one factors in that De Kock, Bavuma, Miller and Du Plessis are still to return, then the South African top order looks to be a place where competition for places will be tough.
There is also the small matter of a possible return to the fray for AB de Villiers.
The selection committee has some difficult decisions ahead of them, but they were given a timely reminder of the credentials of former skipper Du Plessis in the IPL on Wednesday.
If there were any thoughts that perhaps the time had come to move on from the 36-year-old, Du Plessis' stunning knock of 95* (60) that helped power Chennai to victory Kolkata went a long way to squashing them.
Du Plessis was superb, hitting nine 4s and four 6s in his majestic stay at the crease, with his exaggerated back-lift that he has referred to as "wood chopping" prominent.
Speaking after the match, Du Plessis acknowledged that this was the best he had felt at the tournament and he also explained his back-lift.
"It's just rhythm," he said.
"The rhythm of the flow of the hands is where I feel where I'm really good or also when I'm a little bit out."
Du Plessis also paid tribute to Chennai captain and Indian legend MS Dhoni.
"I'm very lucky hat I've been playing under MS for a long time," said Du Plessis.
"It's always really good to have him out there and having a really cool, calm and collected head. He knows what he's doing and it's a pleasure to play under him."