Cape Town - Morne Morkel and Temba Bavuma are in line to return to the Proteas side for the third Test against Australia.
It is particularly significant for Morkel, who has 297 Test wickets to his name and has announced that he will retire from international cricket at the end of the series.
His path back to the side has been made possible by 21-year-old Lungi Ngidi struggling with a toe injury.
Ngidi came in for Morkel in the second Test in Port Elizabeth and was impressive, picking up five wickets in the match as South Africa won by six wickets to level the series.
Morkel, meanwhile, was not at his best during the first Test in Durban, though he did pick up three quick, late wickets in the second innings.
"Lungi bowled really well in the previous game but he’s also got a little bit of a toe problem which is probably why the consideration is happening," Du Plessis explained at Newlands on the eve of the third Test.
"I don’t know exactly what it is, but it is bothering him and keeping him back a bit. If he is not 100% then it is obviously an easy decision for us."
Du Plessis added that it would be "nice" for Morkel to get the opportunity to become only the fifth South African to get to 300 wickets, but there are more important factors at play in the selection.
"What counts in Morne’s favour is that he is a fit bowler and can bowl long spells," Du Plessis explained.
"That’s really important going into this Test match, especially if we have three seamers and a spinner. We’ll have our three bowlers that have the biggest tanks when it comes to bowling a lot of overs."
The other major selection decision is in the top order, where a fit-again Bavuma is in the running to replace Theunis de Bruyn.
Bavuma has been battling a hand injury, and in his absence De Bruyn has been given an opportunity.
He hasn't made the most of it, and in two Tests so far this series De Bruyn has scored just 58 runs at an average of 19.33.
"We’ve got a lot of confidence in Temba," Du Plessis said.
"We know he’s a high-quality player. Obviously, he hasn’t got a lot of cricket under his belt, but the quality is there.
"It’s a good ground for him so he’ll reflect on that confidence and just bring it back into the game."
Du Plessis was referring to Bavuma's first and only century, which came against England at Newlands in 2016.
Bavuma, though, has not played since January 17 when he scored 65 for the Cape Cobras against the Knights in a One Day Cup game.
Du Plessis doesn't view that as an issue.
"I think it’s different for batsmen than it is for bowlers," Du Plessis said of a lack of game time.
"Ideally, you’d like guys to play cricket after an injury to get themselves back into form or time in the middle.
"It doesn’t always work like that. Myself as an example, there wasn’t enough time for me to play a game before the first Test after my injury.
"Temba hasn’t played cricket, but he looks good in the nets for a while and his hand is fully recovered."
Duanne Olivier and Chris Morris, meanwhile, have been released from the squad to play in the last round of Sunfoil Series matches.