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Jethro Rosies

Brasa Belgium

W–L
6–5
Won and lost rating-eligible matches in the past 12 months.
Gi
1,401
Rating based on Gi matches in the past 12 months.
No-Gi
1,139
Rating based on No-Gi matches in the past 12 months.
Current form
5–5
Results from the ten most recent rating-eligible matches.
Opponents
10
Unique opponents faced in rating-eligible matches in the past 12 months.

Honours

Medals and placements

Gold
2
Silver
6
Bronze
3
Total medals
11
Events with results
10

Full career record

Wins
12
Losses
21
Matches
33
Win rate
36.4%

Ways of winning

Submission
4
Points
8
Decision
0
Disqualification
0

Personal records

Longest winning streak
4
Longest submission streak
2
Largest recorded points win
15–0

Recent recorded placements

  3. Lion Cub Jiu Jitsu Competition 5

    NL Event record 1–3

    • Boys GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 kg
    • Boys NO-GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 & -75 kg

12-month performance profile

How the results were achieved

Past 12 months
Current win streak
0
Unique opponents
10
Distinct events
3

Ways of winning

  • Submission 2 33%
  • Points 4 67%
  • Decision 0 0%
  • Other recorded result 0 0%

Gi versus No-Gi

Gi

Rating
1401
Record
6–3
Win rate
67%
Submission share
33%

No-Gi

Rating
1139
Record
0–2
Win rate
0%
Submission share
-

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
1,398
Change over 90 days
-
Highest rating in 12 months
1,388
Performance versus expectation
+4.0 pp
Schedule strength
Top 8%
Average opponent rating
1,411
Weighted win rate
53%
Expected win rate
49%
Repeat-opponent share
9%
Effective evidence
8.5
Confidence
89/100

Opponents

Opposition and rivalries

The strongest recorded win, rematches and opponents faced repeatedly.

Rematches 2–10 2–10 across 12 rematches against 5 repeat opponents.

Top 10 highest-ranked defeated opponents

Past 12 months

  1. #392 Zedek Vroon · The Future League 8 – Gi & No-Gi Pts 5–0
  2. #611 Lennon Van Rooijen · The Future League 8 – Gi & No-Gi Pts 15–0

Full career

  1. #392 Zedek Vroon · The Future League 8 – Gi & No-Gi Pts 5–0
  2. #611 Lennon Van Rooijen · The Future League 8 – Gi & No-Gi Pts 15–0

Rivals

Opponent Head-to-head record Matches
Cristiano Luis 0–4 4
Archie Harcarik 0–2 2
Joël Noten 0–2 2

Recent tournaments

  1. The Future League 8 – Gi & No-Gi

    November 30, 2025 · 21 ; Gi · ≤37 kg
    Gi 5–2

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 +3 Rating 1,398

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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.

July 2026 No new matches Change 0 Rating 1,395

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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.

June 2026 No new matches Change -3 Rating 1,395

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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.

May 2026 No new matches Change +10 Rating 1,398

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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.

April 2026 No new matches Change -3 Rating 1,388

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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.

March 2026 No new matches Change +4 Rating 1,391

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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.

February 2026 No new matches Change +4 Rating 1,387

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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 -1 Rating 1,383

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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 -4 Rating 1,384

Rating-period composition

Rating matches
11 0
Record
6–5 Previous month 6–5
Opponents
10 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 7 new matches Change +116 Rating 1,388

Rating-period composition

Rating matches
11 +7
Record
6–5 Previous month 1–3
Opponents
10 +7
Events
3 +2

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 30, 2025 Piotr Lobos
The Future League 8 – Gi & No-Gi Gi-37
Method Submission 01:37 0–0
Marginal influence -12
Win
November 30, 2025 Zedek Vroon
The Future League 8 – Gi & No-Gi Gi-37
Method Points 03:00 5–0
Marginal influence +14
Win
November 30, 2025 Joao Paulo Lelles
The Future League 8 – Gi & No-Gi Gi-37
Method Points 03:00 2–0
Marginal influence +17
Win
November 30, 2025 Lennon Van Rooijen
The Future League 8 – Gi & No-Gi Gi-37
Method Points 03:00 15–0
Marginal influence +13
Win
November 22, 2025 Ousama Medani
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS Boys Youth Gi / Orange & Green / 13-15 / -64,0 kg (Feather)
Method Submission 03:16 2–0
Marginal influence +15
Win
November 22, 2025 Giel Bouchez
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS Boys Youth Gi / Orange & Green / 13-15 / -64,0 kg (Feather)
Method Submission 00:54 0–0
Marginal influence +12
Loss
November 22, 2025 Ibrahim Ozkezer
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS Boys Youth Gi / Orange & Green / 13-15 / -64,0 kg (Feather)
Method Points 04:00 0–11
Marginal influence -14
October 2025 4 new matches Change Starting point Rating 1,272

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 Cristiano Luis
Lion Cub Jiu Jitsu Competition 5 Boys NO-GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 & -75 kg
Method Submission 02:24 0–2
Marginal influence -17
Loss
October 25, 2025 Achilles Rademaker
Lion Cub Jiu Jitsu Competition 5 Boys NO-GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 & -75 kg
Method Submission 01:46 0–9
Marginal influence -15
Loss
October 25, 2025 Cristiano Luis
Lion Cub Jiu Jitsu Competition 5 Boys GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 kg
Method Submission 01:54 0–0
Marginal influence -15
Win
October 25, 2025 Marcos Belchior
Lion Cub Jiu Jitsu Competition 5 Boys GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 kg
Method Points 2–0
Marginal influence +23
Relevant matches
8.5
Official ranking percentile
-
Performance
4.0 pp above expectation

8.5 weighted matches against 10 different opponents across 3 events

Weighted win rate
53.3%
Expected win rate
49.4%
Average opponent rating
1,411
Repeated-opponent share
9.1%
Network connectivity
87.6%

Classification evidence

Why U18?

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

  • U18 1 event vote Selected outcome

Registrations and outcomes

The Future League 8 – Gi & No-Gi
U18 · Counts
21
  • Competition age 15
  • Registered age: u16
  • Source category: u16
Gi-37
  • Competition age 15
  • Registered age: u16
  • Source category: u16
BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS
Does not count
Boys Youth Gi / Orange & Green / 13-15 / -64,0 kg (Feather)
  • Competition age 15
Lion Cub Jiu Jitsu Competition 5
Does not count
Boys NO-GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 & -75 kg
  • Competition age 15
  • Registered age: u16
  • Source category: u16
Boys GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 kg
  • Competition age 15
  • Registered age: u16
  • Source category: u16

Classification evidence

Why ≤ 65 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

  • ≤ 65 kg 1 competition event Selected outcome

Registrations and outcomes

The Future League 8 – Gi & No-Gi
Does not count
21

No matches in the rating period · no valid weight evidence

The Future League 8 – Gi & No-Gi
Does not count
Gi-37

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

BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS
Does not count
Boys Youth Gi / Orange & Green / 13-15 / -64,0 kg (Feather)

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

Lion Cub Jiu Jitsu Competition 5
≤ 65 kg · Counts as a competition event
Boys NO-GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 & -75 kg
  • Registered weight class: -65 kg
  • Source competition limit: -65 kg

2 matches in the rating period

Lion Cub Jiu Jitsu Competition 5
≤ 65 kg · Counts as a competition event
Boys GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 kg
  • Registered weight class: -65 kg
  • Source competition limit: -65 kg

2 matches in the rating period

Classification evidence

Why Orange?

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

  • orange 4 matches in the rating period Selected outcome
  • green 3 matches in the rating period

Registrations and outcomes

BELGIAN CHAMPIONSHIP GI KIDS YOUTH & ADULTS / CHAMPIONNAT DE BELGIQUE GI KIDS YOUTH & ADULTS
green · Counts as a match
Boys Youth Gi / Orange & Green / 13-15 / -64,0 kg (Feather)
  • Source belt category: green

3 matches in the rating period

Lion Cub Jiu Jitsu Competition 5
orange · Counts as a match
Boys NO-GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 & -75 kg
  • Source belt category: orange

2 matches in the rating period

Lion Cub Jiu Jitsu Competition 5
orange · Counts as a match
Boys GI / 14 & 15 years old (DAY 1: Saturday) / Orange belt / -65 kg
  • Source belt category: orange

2 matches in the rating period