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Arjen Koscielski

Inside Position Academy

W–L
0–4
Won and lost rating-eligible matches in the past 12 months.
Gi
1,128
Rating based on Gi matches in the past 12 months.
No-Gi
1,140
Rating based on No-Gi matches in the past 12 months.
Current form
0–4
Results from the ten most recent rating-eligible matches.
Opponents
2
Unique opponents faced in rating-eligible matches in the past 12 months.

Honours

Medals and placements

Gold
0
Silver
2
Bronze
0
Total medals
2
Events with results
1

Full career record

Wins
0
Losses
4
Matches
4
Win rate
0.0%

Ways of winning

Submission
0
Points
0
Decision
0
Disqualification
0

Recent recorded placements

  1. 2026 AGF Hamburg Summer Open

    DE Event record 0–4

    • No Gi Kids / Boys / Pre Teen (10 - 11 yrs) / White / Feather II (Up to 34.00 kg)
    • Gi Kids / Boys / Kids (8 - 9 yrs) / White / Feather III (Up to 38.60 kg)

12-month performance profile

How the results were achieved

Past 12 months
Current win streak
0
Unique opponents
2
Distinct events
1

Ways of winning

  • Submission 0
  • Points 0
  • Decision 0
  • Other recorded result 0

Gi versus No-Gi

Gi

Rating
1128
Record
0–2
Win rate
0%
Submission share
-

No-Gi

Rating
1140
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
1,227
Change over 90 days
-
Highest rating in 12 months
1,224
Performance versus expectation
-
Schedule strength
-
Average opponent rating
1,443
Weighted win rate
-
Expected win rate
-
Repeat-opponent share
50%
Effective evidence
2.4
Confidence
45/100

Opponents

Opposition and rivalries

The strongest recorded win, rematches and opponents faced repeatedly.

Rematches 0–4 0–4 across 4 rematches against 2 repeat opponents.

Rivals

Opponent Head-to-head record Matches
Noah Abdul 0–2 2

Recent tournaments

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 1,227

Rating-period composition

Rating matches
4 0
Record
0–4 Previous month 0–4
Opponents
2 0
Events
1 0

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

July 2026 4 new matches Change Starting point Rating 1,224

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
July 4, 2026 Hudayfa Öztürk
2026 AGF Hamburg Summer Open No Gi Kids / Boys / Pre Teen (10 - 11 yrs) / White / Feather II (Up to 34.00 kg)
Method Submission 00:54 1–0
Marginal influence -3
Loss
July 4, 2026 Hudayfa Öztürk
2026 AGF Hamburg Summer Open No Gi Kids / Boys / Pre Teen (10 - 11 yrs) / White / Feather II (Up to 34.00 kg)
Method Submission 00:16 0–4
Marginal influence -3
Loss
July 4, 2026 Noah Abdul
2026 AGF Hamburg Summer Open Gi Kids / Boys / Kids (8 - 9 yrs) / White / Feather III (Up to 38.60 kg)
Method Disqualification 0–0
Marginal influence -12
Loss
July 4, 2026 Noah Abdul
2026 AGF Hamburg Summer Open Gi Kids / Boys / Kids (8 - 9 yrs) / White / Feather III (Up to 38.60 kg)
Method Decision 00:11 0–0
Marginal influence -12
Relevant matches
2.4
Official ranking percentile
-
Performance
-

2.4 weighted matches against 2 different opponents across 1 events

Weighted win rate
-
Expected win rate
-
Average opponent rating
1,443
Repeated-opponent share
50.0%
Network connectivity
87.6%

Classification evidence

Why U10?

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

  • U10 1 event vote Selected outcome

Registrations and outcomes

2026 AGF Hamburg Summer Open
U10 · Counts
No Gi Kids / Boys / Pre Teen (10 - 11 yrs) / White / Feather II (Up to 34.00 kg)
  • Competition age 9
  • Registered age: u12
  • Source category: u12
Gi Kids / Boys / Kids (8 - 9 yrs) / White / Feather III (Up to 38.60 kg)
  • Competition age 9
  • Registered age: u10
  • Source category: u10

Classification evidence

Why White?

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

  • white 4 matches in the rating period Selected outcome

Registrations and outcomes

2026 AGF Hamburg Summer Open
white · Counts as a match
No Gi Kids / Boys / Pre Teen (10 - 11 yrs) / White / Feather II (Up to 34.00 kg)
  • Source belt category: white

2 matches in the rating period

2026 AGF Hamburg Summer Open
white · Counts as a match
Gi Kids / Boys / Kids (8 - 9 yrs) / White / Feather III (Up to 38.60 kg)
  • Source belt category: white

2 matches in the rating period