PLAYER PAGE

Mari Grobbelaar

2160158380
Tshwane (GTP)
Personal
Main rating
Rating 1372.4
K-factor 32
Floor 970.3
Highest 1490.2 (2026-01-01)
Min/Max +/- allowed 110
Rating Change
()
Games 9
Score 4.5
We 3.64
SWe 0.86
Temp +/- 27.4
Penalties 0
Weight perform 1325.6
Final +/- +27.4
New Rating
()
Rating 1399.9
K-factor 32
Floor 970.3
Highest 1490.2 (2026-01-01)
Min/Max +/- allowed 109.7
Standard rating
Rating 1369.4
K-factor 32
Floor 978
Highest 1488.2 (2026-01-01)
Min/Max +/- allowed 110
Rating Change
()
Games 9
Score 4.5
We 3.57
SWe 0.93
Temp +/- 29.6
Penalties 0
Weight perform 1325.6
Final +/- +29.6
New Rating
()
Rating 1399
K-factor 32
Floor 978
Highest 1488.2 (2026-01-01)
Min/Max +/- allowed 110
Rapid rating
Rating 1255.4
K-factor 36
Floor 755.4
Highest 1455.5 (2023-09-01)
Min/Max +/- allowed 115.2
Rating Change
()
Games 0
Score 0
We 0
SWe 0
Temp +/- 0
Penalties 0
Weight perform 0
Final +/- 0
New Rating
()
Rating 1255.4
K-factor 36
Floor 755.4
Highest 1455.5 (2023-09-01)
Min/Max +/- allowed 115.2
Blitz rating
Rating 1200
K-factor 36
Floor 700
Highest 1200 (2018-10-01)
Min/Max +/- allowed 165.8
Rating Change
()
Games 0
Score 0
We 0
SWe 0
Temp +/- 0
Penalties 0
Weight perform 0
Final +/- 0
New Rating
()
Rating 1200
K-factor 36
Floor 700
Highest 1200 (2018-10-01)
Min/Max +/- allowed 165.8
Rating Graph
Tournaments
# Tournament Type Start End Host Rounds Rating Games Score Perform Rat+/- Details
1 South African Junior Closed Chess Championship 2026 (U10 Girls) Classical 2026-03-28 2026-04-02 Bojanala Platina (NBR) 9 1372.4 9 4.5 1450.3 27.4 Details
# Tournament Type Start End Host Rounds Rating Games Score Perform Rat+/- Details
1 2026 Blou Bull Chess Tournament (U12) Standard 2026-02-21 2026-02-21 Tshwane (GTP) 5 1379.2 5 3 1464.8 12.3 Details
2 2026 AHS Chess Tournament (U12) Standard 2026-02-28 2026-02-28 Tshwane (GTP) 5 1379.2 5 2.5 1248.8 -19.1 Details
3 2026 Piet Robbertse Open Chess Tournament (C) Standard 2026-02-07 2026-02-08 Tshwane (GTP) 5 1474.2 5 1 1109 -39.7 Details
4 2026 Tshwane Chess Registration Tournament (U12-2) Standard 2026-01-31 2026-01-31 Tshwane (GTP) 5 1474.2 5 2.5 1287.5 -17.3 Details
5 2025 Mzansi Individual Championships (U10 Girls) Classical 2025-12-17 2025-12-20 Nelson Mandela Bay (ENM) 6 1376.6 6 4 1458.7 11.6 Details
6 2025 Mzansi Inter Provincial Team Championships (U10 Combined) Standard 2025-12-15 2025-12-17 Nelson Mandela Bay (ENM) 6 1376.6 6 4.5 1448 8.5 Details
7 Gauteng Inter-Region at Emerald Resort 2025 (U8+U10 Girls) Standard 2025-12-06 2025-12-07 Sedibeng (GSV) 5 1376.6 5 5 1673.1 32.1 Details
8 2025 Centurion Chess Open Tournament (U10) Standard 2025-09-27 2025-09-27 Tshwane (GTP) 5 1324.7 5 3.5 1628.5 28.9 Details
9 2025 Tshwane South School District CLOSED League Championship (U9A) Standard 2025-08-15 2025-08-15 Tshwane (GTP) 5 1346.3 5 1.5 1260.9 -7.8 Details
10 2025 Etienne Lewis Closed Chess Tournament (U10) Standard 2025-08-08 2025-08-10 Tshwane (GTP) 7 1346.3 7 3.5 1313.2 -4.3 Details
11 2025 Wynie Robbertse Chess Tournament (U10) Standard 2025-07-19 2025-07-19 Tshwane (GTP) 5 1312.9 5 2.5 1283.8 -3.5 Details
12 South African Open 2025 (U10 Girls) Classical 2025-07-03 2025-07-05 Johannesburg Metro (GJM) 5 1312.9 5 4 1506.9 22 Details
13 Third Knight Riders Junior Open 2025 (U10) Standard 2025-06-22 2025-06-22 Johannesburg Metro (GJM) 5 1311.4 5 3 1326.4 0.8 Details
14 2025 Silver Lakes Chess Club Open Chess Tournament (U10) Standard 2025-05-03 2025-05-03 Tshwane (GTP) 5 1311.1 5 2.5 1289.5 -2.8 Details
15 Lubowski Open 2025 (D2) Standard 2025-03-21 2025-03-22 Tshwane (GTP) 5 1355.7 5 3 1302.4 -6.6 Details
16 2025 Chris Greyling Open Chess Tournament (U10) Standard 2025-03-15 2025-03-15 Tshwane (GTP) 5 1355.7 5 1.5 1105.1 -25.1 Details
17 Constantiapark Open 2025 (U10) Standard 2025-02-15 2025-02-15 Tshwane (GTP) 5 1338.3 5 4 1507.3 17.3 Details
18 2025 Blou Bul Open Chess Tournament (D2) Standard 2025-02-08 2025-02-08 Tshwane (GTP) 5 1338.3 5 2 1172.2 -16.8 Details
19 2025 Tshwane Chess OPEN Registration Tournament (U10) Standard 2025-01-25 2025-01-25 Tshwane (GTP) 5 1318.2 5 3 1401.4 8.8 Details
20 Gauteng Inter-Region at UJ 2024 (u10 gIRLS) Standard 2024-12-07 2024-12-08 Johannesburg Metro (GJM) 5 1294.2 5 3 1407.4 13.3 Details
21 Lardies Ope 2024 (U10) Standard 2024-10-26 2024-10-26 Tshwane (GTP) 5 1281.1 5 3 1349.2 7.3 Details
22 2024 Tuks Open Chess Tournament (U10) Standard 2024-09-28 2024-09-28 Tshwane (GTP) 5 1277.4 5 2 1271.3 0.2 Details
23 2024 Etienne Lewis (U10) Standard 2024-08-30 2024-09-01 Tshwane (GTP) 7 1277.4 7 4 1282.9 1.9 Details
24 Menlopark Open Chess Tournament 2024 (U10) Standard 2024-07-13 2024-07-13 Tshwane (GTP) 5 1246.3 5 3.5 1416.3 17.3 Details
25 2024 African Youth Chess Championship Classical 2024-06-16 2024-06-22 Tshwane (GTP) 9 1309.9 9 5 1221.4 -9.6 Details
26 2024 Johannes Mabusela's 40th Birthday Chess Tournament F Section (D) Standard 2024-06-01 2024-06-01 Tshwane (GTP) 5 1309.9 5 2 1049.7 -25.7 Details
27 2024 Tshwane South School District CLOSED Individual Championships (U11 Girls) Standard 2024-05-11 2024-05-11 Tshwane (GTP) 5 1334.2 5 2 1118.6 -20.1 Details
28 South African Junior Closed Chess Championship 2024 (U8 Girls) Classical 2024-04-27 2024-05-01 Ekurhuleni (GE) 9 1334.2 9 6 1369.9 6.6 Details
29 2024 Lubowski Open Chess Tournament (D2) Standard 2024-03-23 2024-03-24 Tshwane (GTP) 5 1353.8 5 3 1260 -10.9 Details
30 2024 Constantiapark Open (E) Standard 2024-02-17 2024-02-17 Tshwane (GTP) 5 1359.2 5 3 1320.6 -3 Details
31 2024 Tshwane Chess OPEN Registration Tournament (E) Standard 2024-01-27 2024-01-27 Tshwane (GTP) 5 1353.2 5 3.5 1323.8 -3.3 Details
32 2024 Gauteng Inter-Region Chess Championship (U8+U10 Girls) Standard 2024-01-13 2024-01-14 Tshwane (GTP) 5 1353.2 4 3 1438.8 6 Details
33 Lardies Open Tournament 2023 (F) Standard 2023-10-28 2023-10-28 Tshwane (GTP) 5 1251.6 5 3 1323.6 7.8 Details
34 2023 Gauteng Noord (F) Standard 2023-10-14 2023-10-14 Tshwane (GTP) 6 1251.6 6 6 1615.6 48.2 Details
35 2023 Centurion Chess Open (E) Standard 2023-09-23 2023-09-23 Tshwane (GTP) 5 1234.8 5 2 1162.6 -6.3 Details
36 2023 U8 Open Chess Tournament Rapid 2023-09-02 2023-09-02 Tshwane (GTP) 5 1234.8 5 4 1447.1 15.6 Details
37 2023 Woman's Day Open Chess Tournament (Pawn) Standard 2023-08-09 2023-08-09 Tshwane (GTP) 5 1219.1 5 3 1351.5 13.6 Details
38 2023 Etienne Lewis Closed Tournament (U8) Standard 2023-08-26 2023-08-26 Tshwane (GTP) 6 1219.1 5 2 1171.3 -4.5 Details
39 2023 Menlo Open Tournament (F) Standard 2023-07-22 2023-07-22 Tshwane (GTP) 5 1200 5 3 1316.9 10.6 Details
Game statistics ( )
Games 0
Wins 0
Draws 0
Losses 0
White 0
Black 0
White wins 0
Black wins 0
Score 0
Percent 0
Dp 0
AOR 0
Performance 0
Game statistics ()
Games 29
Wins 12
Draws 3
Losses 14
White 13
Black 16
White wins 5
Black wins 7
Score 13.5
Percent 46.6
Dp -29.3
AOR 1360.4
Performance 1331.1
Game statistics (History)
Games 218
Wins 120
Draws 14
Losses 84
White 107
Black 111
White wins 61
Black wins 59
Score 127
Percent 58.3
Dp 70.2
AOR 1268
Performance 1338.2
Rankings (Main)
National
Overall 4035
Gender 661
Age group 341
Gender/Age 83
Provincial
Overall 1362
Gender 214
Age group 113
Gender/Age 20
Regional
Overall 481
Gender 90
Age group 38
Gender/Age 12
Rankings (Standard)
National
Overall 3684
Gender 622
Age group 313
Gender/Age 74
Provincial
Overall 1287
Gender 204
Age group 109
Gender/Age 19
Regional
Overall 476
Gender 87
Age group 38
Gender/Age 11
Rankings (Rapid)
National
Overall -1
Gender -1
Age group -1
Gender/Age -1
Provincial
Overall -1
Gender -1
Age group -1
Gender/Age -1
Regional
Overall -1
Gender -1
Age group -1
Gender/Age -1
Rankings (Blitz)
National
Overall -1
Gender -1
Age group -1
Gender/Age -1
Provincial
Overall -1
Gender -1
Age group -1
Gender/Age -1
Regional
Overall -1
Gender -1
Age group -1
Gender/Age -1
Performance ( )
Games 9
Score 4.5
Percent 50
Aor 1450.3
Dp 0
Prat 1450.3
Performance ()
Games 29
Score 13.5
Percent 46.6
Aor 1360.4
Dp -29.3
Prat 1331.1
Performance (12 months)
Games 83
Score 47.5
Percent 57.2
Aor 1325.1
Dp 61.4
Prat 1386.5
Performance (History)
Games 218
Score 127
Percent 58.3
Aor 1268
Dp 70.2
Prat 1338.2
Top 5 opponents most often played
Type # Opponent Games White Black First tournament Last tournament Details
Overall 1 Westermann, Z (Zelri) 7 1 6 2023 Gauteng Noord (F) 2026 AHS Chess Tournament (U12) Details
Overall 2 Barkhuizen, RJ (Reuben Joshua) 5 2 3 2023 Etienne Lewis Closed Tournament (U8) 2025 Tshwane Chess OPEN Registration Tournament (U10) Details
Overall 3 Rocher, G (Gideon) 4 3 1 2023 Menlo Open Tournament (F) Lardies Open Tournament 2023 (F) Details
Overall 4 Roos, B (Benjamin) 4 2 2 2023 Etienne Lewis Closed Tournament (U8) 2025 Tshwane South School District CLOSED League Championship (U9A) Details
Overall 5 Nawrattel, A (Abigail) 4 1 3 2023 Gauteng Noord (F) 2025 Wynie Robbertse Chess Tournament (U10) Details
Standard 1 Westermann, Z (Zelri) 7 1 6 2023 Gauteng Noord (F) 2026 AHS Chess Tournament (U12) Details
Standard 2 Barkhuizen, RJ (Reuben Joshua) 5 2 3 2023 Etienne Lewis Closed Tournament (U8) 2025 Tshwane Chess OPEN Registration Tournament (U10) Details
Standard 3 Rocher, G (Gideon) 4 3 1 2023 Menlo Open Tournament (F) Lardies Open Tournament 2023 (F) Details
Standard 4 Roos, B (Benjamin) 4 2 2 2023 Etienne Lewis Closed Tournament (U8) 2025 Tshwane South School District CLOSED League Championship (U9A) Details
Standard 5 Nawrattel, A (Abigail) 4 1 3 2023 Gauteng Noord (F) 2025 Wynie Robbertse Chess Tournament (U10) Details