HTS Louis Botha have replaced Affies at No 20 on the FNB rankings following their 41-22 win over Sentraal.
Affies' disappointing season continued when they lost 37-10 to Maritzburg College.
Paul Roos were rewarded for their 24-11 win over Oakdale, jumping two places from sixth to fourth, relegating EG Jansen to sixth, while Middelburg remain at No 5.
In the only other change, Paarl Boys' and Waterkloof swap in the seventh and eighth spots after Boishaai hammered Bishops 36-3.
FNB Top 20 rankings
1. Grey College
2. Monument
3. Garsfontein
4. Paul Roos
5. HTS Middelburg
6. EG Jansen
7. Paarl Boys'
8. Waterkloof
9. Glenwood
10. Selborne
11. Grey High
12. Menlopark
13. Wynberg
14. Maritzburg
15. Oakdale
16. Outeniqua
17. Paarl Gym
18. Nelspruit
19. Michaelhouse
20. HTS Louis Botha
Over at SASchoolSports.co.za, Glenwood slip down two places from sixth to eighth, having been beaten 29-12 by Grey College, who stretched their unbeaten streak to 23 matches.
The heavy defeat against Paarl Boys' sees Bishops relinquish their top 10 status, slipping from ninth to 15th, while Voortrekker Bethlehem replace Kempton Park in the rankings.
SA School Sports Top 20 rankings
1. Grey College
2. Garsfontein
3. Paul Roos
4. Monument
5. Selborne
6. EG Jansen
7. Paarl Boys'
8. Glenwood
9. Grey High
10. HTS Middelburg
11. Paarl Gym
12. Menlopark
13. Maritzburg
14. Michaelhouse
15. Bishops
16. Outeniqua
17. Wynberg
18. Waterkloof
19. Westville
20. Voortrekker Bethlehem
Sources: Rugby365.com/SASchoolSports.co.za
Photo: Johan Pretorius/Gallo Images