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Joah Duff

Kampfsportzentrum Winterthur

W–L
0–3
Won and lost rating-eligible matches in the past 12 months.
Gi
1,125
Rating based on Gi matches in the past 12 months.
No-Gi
1,116
Rating based on No-Gi matches in the past 12 months.
Current form
0–3
Results from the ten most recent rating-eligible matches.
Opponents
3
Unique opponents faced in rating-eligible matches in the past 12 months.

Indexed career

Matches

3
Indexed competition matches
Date Opponent Result Event Division
2026-03-21 Xavi Martinez
Loss
Zurich BJJ SPRING OPEN GI and NO-GI 2026 Gi · BOYS GI / Infant / Grey / -30kg
2025-11-23 Levin Marthaler
Loss
ADCC Suisse Open Championship 2025 No-Gi · BOYS / 9-10 years / Beginner / -32 kg
2025-11-23 Diego Anael Lima Pereira Alves Araújo Júnior
Loss
ADCC Suisse Open Championship 2025 No-Gi · BOYS / 9-10 years / Beginner / -32 kg

Calculation details

Rating breakdown for the past 12 months

Rating calculations are being updated. Current event, match and opponent details remain visible.

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 1 event vote Selected outcome

Registrations and outcomes

Zurich BJJ SPRING OPEN GI and NO-GI 2026
U12 · Counts
BOYS GI / Infant / Grey / -30kg
  • Competition age 11
  • Registered age: u12
  • Source category: u12
ADCC Suisse Open Championship 2025
Does not count
BOYS / 9-10 years / Beginner / -32 kg
  • Competition age 10

Classification evidence

Why ≤ 30 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

  • ≤ 30 kg 1 competition event Selected outcome
  • ≤ 32 kg 1 competition event

Registrations and outcomes

Zurich BJJ SPRING OPEN GI and NO-GI 2026
≤ 30 kg · Counts as a competition event
BOYS GI / Infant / Grey / -30kg
  • Registered weight class: -30kg
  • Source competition limit: -30kg

1 match in the rating period

ADCC Suisse Open Championship 2025
≤ 32 kg · Counts as a competition event
BOYS / 9-10 years / Beginner / -32 kg
  • Registered weight class: -32 kg
  • Source competition limit: -32 kg

2 matches in the rating period

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 1 match in the rating period Selected outcome

Registrations and outcomes

Zurich BJJ SPRING OPEN GI and NO-GI 2026
grey · Counts as a match
BOYS GI / Infant / Grey / -30kg
  • Source belt category: grey

1 match in the rating period