South African batsman Dean Elgar withdrew injured from the third Test against India after being hit on the helmet by a short pitched delivery Monday.
The impact off the ball from pace bowler Umesh Yadav left the opener on the ground, shaken.
A physio was called for and the umpires announced an early tea. Elgar eventually retired hurt on 16 and Theunis de Bruyn was brought in as a concussion sub.
Cricket South Africa later announced that Elgar "will not take any further part in this Test match".
The International Cricket Council (ICC) approved the use of concussion substitutes for all internationals from August with de Bryun becoming the third sub to be used.
Australia's Marnus Labuschagne came in for Steve Smith in the second Ashes Test. West Indies brought in Jermaine Blackwood after Darren Bravo retired hurt in the Jamaica Test against India last Month.