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Sebastian Hermans

Brasa Belgium

W–L
11–8
Won and lost rating-eligible matches in the past 12 months.
Gi
1,296
Rating based on Gi matches in the past 12 months.
No-Gi
1,394
Rating based on No-Gi matches in the past 12 months.
Current form
7–3
Results from the ten most recent rating-eligible matches.
Opponents
16
Unique opponents faced in rating-eligible matches in the past 12 months.

Honours

Medals and placements

Gold
1
Silver
4
Bronze
5
Total medals
10
Events with results
10

Full career record

Wins
21
Losses
25
Matches
46
Win rate
45.7%

Ways of winning

Submission
6
Points
12
Decision
1
Disqualification
1

Personal records

Longest winning streak
6
Longest submission streak
2
Largest recorded points win
21–0

Recent recorded placements

  5. Lion Cub Jiu Jitsu Competition 5

    NL Event record 4–4

    • Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
    • Boys GI / 10 & 11 years old (DAY 1: Saturday) / Grey belt / -38 kg

12-month performance profile

How the results were achieved

Past 12 months
Current win streak
0
Unique opponents
16
Distinct events
4

Ways of winning

  • Submission 5 45%
  • Points 4 36%
  • Decision 1 9%
  • Other recorded result 1 9%

Gi versus No-Gi

Gi

Rating
1296
Record
4–5
Win rate
44%
Submission share
75%

No-Gi

Rating
1394
Record
7–3
Win rate
70%
Submission share
29%

Win quality

Grouped by pre-match win probability. This provides context and does not award an extra rating bonus.

As underdog 0–0 Less than 35% expected win probability before the match.
Even match 0–0 Between 35% and 65% expected win probability before the match.
As favourite 0–0 More than 65% expected win probability before the match.

Development

Rating and development

The same published rating, supported by trend, opponent strength and evidence quality.

Current rating
1,411
Change over 90 days
+49
Highest rating in 12 months
1,415
Performance versus expectation
+6.1 pp
Schedule strength
Top 41%
Average opponent rating
1,338
Weighted win rate
60%
Expected win rate
54%
Repeat-opponent share
16%
Effective evidence
13.8
Confidence
95/100

Opponents

Opposition and rivalries

The strongest recorded win, rematches and opponents faced repeatedly.

Rematches 9–11 9–11 across 20 rematches against 8 repeat opponents.

Top 10 highest-ranked defeated opponents

Past 12 months

  1. #425 Luca Oprea · The Future League 9 - Gi & NoGi Sub 02:08 6–0 Earlier · Sub 02:11 2–0 March 22, 2026 · The Future League 9 - Gi & NoGi
  2. #542 Dex Van Rijswijck · Lion Cub Jiu Jitsu Competition 5 Pts 5–2
  3. #649 Jamie Van Der Arend · The Future League 9 - Gi & NoGi Sub 02:50 5–0
  4. #791 Emma Petrovic · The Future League 9 - Gi & NoGi Pts 8–0
  5. #896 Alexander Wouters · The Future League 9 - Gi & NoGi Dec 0–0

Full career

  1. #347 Maximus Lee · Lion Cub Jiu Jitsu Competition 4 Pts 2–0
  2. #425 Luca Oprea · The Future League 9 - Gi & NoGi Sub 02:08 6–0 Earlier · Sub 02:11 2–0 March 22, 2026 · The Future League 9 - Gi & NoGi
  3. #542 Dex Van Rijswijck · Lion Cub Jiu Jitsu Competition 5 Pts 5–2
  4. #649 Jamie Van Der Arend · The Future League 9 - Gi & NoGi Sub 02:50 5–0
  5. #791 Emma Petrovic · The Future League 9 - Gi & NoGi Pts 8–0
  6. #896 Alexander Wouters · The Future League 9 - Gi & NoGi Dec 0–0
  7. #1433 Yven Tesser · VERSUS 'The Future League' 3 (kids & teens) Pts 2–0

Rivals

Opponent Head-to-head record Matches
Alec Besems 1–4 5
ARIF Aymen 0–2 2

Around this athlete

Athlete Rank Rating
Leonardo Brito #352 1,411
Sebastian Hermans #353 1,411
Imed Boudrouma #354 1,410

Scheduled

Recent tournaments

  3. The Future League 8 – Gi & No-Gi

    November 30, 2025 · 15 ; Gi · ≤19 kg
    Gi 0–5

Calculation details

Rating breakdown for the past 12 months

See the published month-end rating and the rating-eligible matches added in each month. Open a month for details.

August 2026 No new matches Change -1 Rating 1,411

Rating-period composition

Rating matches
19 0
Record
11–8 Previous month 11–8
Opponents
16 0
Events
4 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

July 2026 No new matches Change 0 Rating 1,412

Rating-period composition

Rating matches
19 0
Record
11–8 Previous month 11–8
Opponents
16 0
Events
4 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

June 2026 No new matches Change -2 Rating 1,412

Rating-period composition

Rating matches
19 0
Record
11–8 Previous month 11–8
Opponents
16 0
Events
4 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

May 2026 No new matches Change -1 Rating 1,414

Rating-period composition

Rating matches
19 0
Record
11–8 Previous month 11–8
Opponents
16 0
Events
4 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

April 2026 3 new matches · 7 left period Change 0 Rating 1,415

Rating-period composition

Rating matches
19 -4
Record
11–8 Previous month 13–10
Opponents
16 -2
Events
4 0

7 older matches left the 12-month period: 4 won and 3 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Loss
April 4, 2026 Omar El Fakiri
NO GI - BELGIAN CHAMPIONSHIP KIDS YOUTH & ADULTS 2026 Boys NoGi / White-Grey / 10-11-12 yrs / -40 kg
Method Points 04:00 0–2
Marginal influence -10
Win
April 4, 2026 Younes Ghanam
NO GI - BELGIAN CHAMPIONSHIP KIDS YOUTH & ADULTS 2026 Boys NoGi / White-Grey / 10-11-12 yrs / -40 kg
Method Points 04:00 8–0
Marginal influence +14
Win
April 4, 2026 Noé Gosamo
NO GI - BELGIAN CHAMPIONSHIP KIDS YOUTH & ADULTS 2026 Boys NoGi / White-Grey / 10-11-12 yrs / -40 kg
Method Disqualification 03:21 16–0
Marginal influence +11
March 2026 6 new matches Change +52 Rating 1,415

Rating-period composition

Rating matches
23 +6
Record
13–10 Previous month 8–9
Opponents
18 +5
Events
4 +1

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
March 22, 2026 Jamie Van Der Arend
The Future League 9 - Gi & NoGi Gi - 40
Method Submission 02:50 5–0
Marginal influence +9
Win
March 22, 2026 Luca Oprea
The Future League 9 - Gi & NoGi Gi - 40
Method Submission 02:08 6–0
Marginal influence +14
Loss
March 22, 2026 Hamza Chouhou
The Future League 9 - Gi & NoGi Gi - 40
Method Submission 01:47 2–0
Marginal influence -8
Win
March 22, 2026 Alexander Wouters
The Future League 9 - Gi & NoGi NoGi - 9
Method Decision 03:00 0–0
Marginal influence +10
Win
March 22, 2026 Emma Petrovic
The Future League 9 - Gi & NoGi NoGi - 9
Method Points 03:00 8–0
Marginal influence +8
Win
March 22, 2026 Luca Oprea
The Future League 9 - Gi & NoGi NoGi - 9
Method Submission 02:11 2–0
Marginal influence +11
February 2026 No new matches Change 0 Rating 1,363

Rating-period composition

Rating matches
17 0
Record
8–9 Previous month 8–9
Opponents
13 0
Events
3 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

January 2026 No new matches Change -3 Rating 1,363

Rating-period composition

Rating matches
17 0
Record
8–9 Previous month 8–9
Opponents
13 0
Events
3 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

December 2025 No new matches Change 0 Rating 1,366

Rating-period composition

Rating matches
17 0
Record
8–9 Previous month 8–9
Opponents
13 0
Events
3 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

November 2025 3 new matches Change 0 Rating 1,366

Rating-period composition

Rating matches
17 +3
Record
8–9 Previous month 7–7
Opponents
13 +2
Events
3 +1

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Loss
November 22, 2025 Hassan Diallo
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS Boys Gi / White-Grey / 10-11-12 yrs / -40 kg
Method Points 04:00 2–17
Marginal influence -13
Loss
November 22, 2025 ARIF Aymen
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS Boys Gi / White-Grey / 10-11-12 yrs / -40 kg
Method Points 04:00 0–7
Marginal influence -15
Win
November 22, 2025 El Bakri Adam
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS Boys Gi / White-Grey / 10-11-12 yrs / -40 kg
Method Points 04:00 13–2
Marginal influence +6
October 2025 7 new matches Change +28 Rating 1,366

Rating-period composition

Rating matches
14 +7
Record
7–7 Previous month 4–3
Opponents
11 +5
Events
2 +1

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Loss
October 25, 2025 Elyaino Lawalata
Lion Cub Jiu Jitsu Competition 5 Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
Method Submission 00:53 0–0
Marginal influence -5
Loss
October 25, 2025 Elyaino Lawalata
Lion Cub Jiu Jitsu Competition 5 Boys GI / 10 & 11 years old (DAY 1: Saturday) / Grey belt / -38 kg
Method Submission 01:24 2–2
Marginal influence -14
Loss
October 25, 2025 Alec Besems
Lion Cub Jiu Jitsu Competition 5 Boys GI / 10 & 11 years old (DAY 1: Saturday) / Grey belt / -38 kg
Method Submission 01:01 0–0
Marginal influence -9
Win
October 25, 2025 Hannes Driftmeier
Lion Cub Jiu Jitsu Competition 5 Boys GI / 10 & 11 years old (DAY 1: Saturday) / Grey belt / -38 kg
Method Submission 00:48 9–0
Marginal influence +6
Loss
October 25, 2025 Elyaino Lawalata
Lion Cub Jiu Jitsu Competition 5 Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
Method Submission 00:11 0–0
Marginal influence -5
Win
October 25, 2025 Dex Van Rijswijck
Lion Cub Jiu Jitsu Competition 5 Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
Method Points 03:00 5–2
Marginal influence +10
Win
October 25, 2025 Zeyd Tarik Ersoy
Lion Cub Jiu Jitsu Competition 5 Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
Method Submission 00:59 6–0
Marginal influence +8
September 2025 No new matches · 2 left period Change +4 Rating 1,338

Rating-period composition

Rating matches
7 -2
Record
4–3 Previous month 4–5
Opponents
6 -2
Events
1 -1

2 older matches left the 12-month period: 0 won and 2 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

Relevant matches
13.8
Official ranking percentile
Top 24%
Performance
6.1 pp above expectation

13.8 weighted matches against 16 different opponents across 4 events

Weighted win rate
60.2%
Expected win rate
54.1%
Average opponent rating
1,338
Repeated-opponent share
15.8%
Network connectivity
87.6%

Classification evidence

Why U12?

Within the published period from 2025-09-01 through 2026-08-31, only competition ages recorded at events in the calculation year determine this outcome, with at most one vote per event. Without such an age, the most recent unambiguous earlier competition age is projected to the calculation year; bracket evidence is the final fallback. The newest evidence breaks a tie.

Evidence outcome

  • U12 2 event votes Selected outcome

Registrations and outcomes

NO GI - BELGIAN CHAMPIONSHIP KIDS YOUTH & ADULTS 2026
U12 · Counts
Boys NoGi / White-Grey / 10-11-12 yrs / -40 kg
  • Competition age 11
The Future League 9 - Gi & NoGi
U12 · Counts
NoGi - 9
  • Competition age 11
  • Registered age: u12
  • Source category: u12
Gi - 40
  • Competition age 11
  • Registered age: u14
  • Source category: u14
The Future League 8 – Gi & No-Gi
Does not count
15
  • Competition age 10
  • Registered age: u14
  • Source category: u14
Gi-19
  • Competition age 10
  • Registered age: u12
  • Source category: u12
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS
Does not count
Boys Gi / White-Grey / 10-11-12 yrs / -40 kg
  • Competition age 10
Lion Cub Jiu Jitsu Competition 5
Does not count
Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
  • Competition age 10
  • Registered age: u12
  • Source category: u12
Boys GI / 10 & 11 years old (DAY 1: Saturday) / Grey belt / -38 kg
  • Competition age 10
  • Registered age: u12
  • Source category: u12

Classification evidence

Why ≤ 40 kg?

This outcome uses at most one unambiguous upper weight limit per completed ranking event from 2025-09-01 through 2026-08-31. Only the three most recent eligible events are considered, and the lightest verified upper limit is selected. A higher division is not treated as measured body weight.

Evidence outcome

  • ≤ 40 kg 2 competition events Selected outcome

Registrations and outcomes

NO GI - BELGIAN CHAMPIONSHIP KIDS YOUTH & ADULTS 2026
≤ 40 kg · Counts as a competition event
Boys NoGi / White-Grey / 10-11-12 yrs / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

3 matches in the rating period

The Future League 9 - Gi & NoGi
Does not count
NoGi - 9

3 matches in the rating period · weight class could not be normalized reliably

The Future League 9 - Gi & NoGi
Does not count
Gi - 40

3 matches in the rating period · weight class could not be normalized reliably

The Future League 8 – Gi & No-Gi
Does not count
15

No matches in the rating period · no valid weight evidence

The Future League 8 – Gi & No-Gi
Does not count
Gi-19

No matches in the rating period · no valid weight evidence

BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS
≤ 40 kg · Counts as a competition event
Boys Gi / White-Grey / 10-11-12 yrs / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

3 matches in the rating period

Lion Cub Jiu Jitsu Competition 5
≤ 42 kg · Does not count
Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
  • Registered weight class: -42 kg
  • Source competition limit: -42 kg

4 matches in the rating period · conflicting upper weight limits make this event ambiguous

Lion Cub Jiu Jitsu Competition 5
≤ 38 kg · Does not count
Boys GI / 10 & 11 years old (DAY 1: Saturday) / Grey belt / -38 kg
  • Registered weight class: -38 kg
  • Source competition limit: -38 kg

3 matches in the rating period · conflicting upper weight limits make this event ambiguous

Classification evidence

Why Grey?

This outcome uses the belt category of every rating-eligible match from 2025-09-01 through 2026-08-31. The most-fought category is selected; the newest evidence breaks a tie.

Evidence outcome

  • grey 10 matches in the rating period Selected outcome
  • yellow 3 matches in the rating period

Registrations and outcomes

NO GI - BELGIAN CHAMPIONSHIP KIDS YOUTH & ADULTS 2026
grey · Counts as a match
Boys NoGi / White-Grey / 10-11-12 yrs / -40 kg
  • Source belt category: grey

3 matches in the rating period

BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS
grey · Counts as a match
Boys Gi / White-Grey / 10-11-12 yrs / -40 kg
  • Source belt category: grey

3 matches in the rating period

Lion Cub Jiu Jitsu Competition 5
yellow · Counts as a match
Boys GI / 10 & 11 years old (DAY 1: Saturday) / Grey belt / -38 kg
  • Source belt category: yellow

3 matches in the rating period

Lion Cub Jiu Jitsu Competition 5
grey · Counts as a match
Boys NO-GI / 10 & 11 years old (DAY 1: Saturday) / White & Grey & Yellow belt / -38 kg
  • Source belt category: grey

4 matches in the rating period