Duminy has been ruled out of the remainder of the ODI series after having suffered a cut on his right hand when fielding in the third game in Rajkot.
After undergoing a medical assessment, it was revealed that Duminy will need between two to three weeks to recover from the injury.
The 31-year-old will however remain with the squad in India with the target of getting fit ahead of the first Test match which will be played on 5th November in Mohali.
Elgar, who is South Africa’s opening batsman in Tests, has only played five ODIs in his career, all of them coming in 2012.
Though the 29-year-old has had an indifferent start to his ODI career, he is currently in a good form in the domestic one-day cup, having scored 143 runs from two innings at an average of 71.50.
South Africa are also sweating on the fitness of their premier fast bowler Morne Morkel, who complained of a discomfort in his quadriceps muscle in the third ODI.
Morkel put in a man of the match performance with four wickets in the third game in Rajkot and is currently the highest wicket-taker in the series with seven scalps.
India are also struck with injury concerns as their lead off-spinner, Ravichandran Ashwin has been ruled out of the remaining two ODIs due to a side strain.
Having taken a 2-1 lead in the third ODI in Rajkot, South Africa will be keen to seal the series victory with a win in the fourth game which will be played in Chennai on 22nd October.
© Cricket World 2015