There were some changes made during the series but the situation is as follows:-
England
Burns - 1 test 93 runs Average per innings 46,5
Sibley - 4 tests 324 runs Average per innings 41,0
Crawley - 3 tests 163 runs Average per innings 27,17
Denly - 4 tests 210 runs Average per innings 26,25
Root - 4 tests 236 runs Average per innings 29.5
Stokes - 4 tests 318 runs Average per innings 39,75
Bairstow - 1 test 10 runs Average per innings 5
Pope - 3 tests 266 runs Average per innings 44,33
South Africa
Elgar - 4 tests 244 runs Average per innings 30,5
Markram - 1 test 22 runs Average per innings 11
Malan - 3 tests 156 runs Average per innings 26
Hamza - 3 tests 78 runs Average per innings 13
Bavuma - 1 test 33 runs Average per innings 16,5
Du Plessis - 4 tests 158 runs Average per innings 19,75
V D Dussen - 4 tests 217 runs Average per innings 27,12
De Kock - 4 tests 380 runs Average per innings 47,5
I am more interested in the SA team. There was 1 player with an above 40 average and one with an average of marginally above 30, One was above 25 - the rest were all below 20.
That is just not good enough, If we look at another side of the story namely 50's made by SA:-
Elgar - 1
Van der Dussen - 3
De Kock - 4
Looking at that the only batsmen who were really up to standard was Van der Dussen and De Kock.