Dean Elgar, batting on 16 in the second innings as South Africa were asked to follow on, was hit flush on the helmet on the side of the head as he took his eyes off the short ball from Umesh Yadav. Elgar spent a lot of time sitting down, looking dazed by the hit. The incident, which happened three overs before Tea, led to an early session break.
on later half of day three Theunis de Bruyn was sent down for batting as replacement of dean elgar. How could South Africa replace a player in a on going match???
The answer to the question lies in the icc concussion rule.according to the concussion rule if a player is hit on the head,the said player can be replaced by a like to like player i.e batsmen will have to be replace by batsmen and bowlers to be replaced by bowlers.
In July 2019, the International Cricket Council (ICC) agreed to allow the use of concussion replacements in all international cricket matches from 1 August 2019, with substitute having to be a “like-for-like replacement” and approved by the Match Referee.The first use of such a substitute was during the Second Test at Lord’s in the 2019 Ashes series between England and Australia, when Steve Smith was hit on the neck by a bouncer by Jofra Archer in the first innings. He was later diagnosed as having suffered concussion and was ruled out of the remainder of the Test. Marnus Labuschagne was named as the official replacement for Smith and came to bat on the final day of the Test.In the second test between India and West Indies,Blackwood was named replacement for an injured DM Bravo and batted in the same innings.