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CZ

Petr Zajíc

OFA

W–L
8–9
Won and lost rating-eligible matches in the past 12 months.
Gi
1,276
Rating based on Gi matches in the past 12 months.
No-Gi
1,293
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
13
Unique opponents faced in rating-eligible matches in the past 12 months.

Tournament history

Events

8
Events
Date Event Result Format Division
TATAMY 19: Czech Open Championship (kids) CZ · Gi · 10–12 yo · white/grey · ≤40 kg ; No-Gi · 10–12 yo · ≤40 kg 3–4 W–L: Win / Loss GiNo-Gi
  • Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
  • Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) CZ · Gi · 10–12 yo · ≤40 kg ; No-Gi · 10–12 yo · ≤40 kg 4–1 W–L: Win / Loss GiNo-Gi
  • Gi / 10-12 years / Boy / -40 kg / Beginner
  • No-Gi / 10-12 years / Boy / -40 kg / Beginners
TATAMY 17 KIDS (No-GI and GI round robin) CZ · Gi · 10–12 yo · white/grey · ≤40 kg ; No-Gi · 10–12 yo · ≤40 kg 2–4 W–L: Win / Loss GiNo-Gi
  • Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
TATAMY 13 KIDS (No-GI and GI round robin) CZ · Gi · 10–12 yo · white/grey · ≤36 kg ; No-Gi · 10–12 yo · ≤36 kg 3–5 W–L: Win / Loss GiNo-Gi
  • Place #4
  • Place #6
NAGA Europe Grappling Championship Germany · No-Gi · 10–11 yo · 30–34.9 kg 1–0 W–L: Win / Loss GiNo-Gi
  • Children Gi (Male) / Beginner / 30 - 34.9 / 10-11 years
  • Children No-Gi (Male) / Beginner / 30 - 34.9 / 10-11 years
NAGA Amsterdam Grappling Championship the Netherlands · Gi · 10–11 yo · 30–34.9 kg ; No-Gi · 10–11 yo · 30–34.9 kg 2–0 W–L: Win / Loss GiNo-Gi
  • Children Gi (Male) / Novice / 30 - 34.9 / 10-11 years
  • Children No-Gi (Male) / Novice / 30 - 34.9 / 10-11 years
TATAMY 9 (No-GI and GI round robin) CZ · Gi · 10–12 yo · white/grey · ≤32 kg ; No-Gi · 10–12 yo · ≤32 kg 1–5 W–L: Win / Loss GiNo-Gi
  • Kids / No Gi / 10-12 years / Boys / Beginner / -32 kg
  • Place #4
ADCC Czech Open 2024 CZ · No-Gi · 9–10 yo · ≤32 kg 0–1 W–L: Win / Loss No-Gi
  • Place #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 0 Rating 1,351

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.

July 2026 No new matches Change +1 Rating 1,351

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.

June 2026 No new matches Change -1 Rating 1,350

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.

May 2026 No new matches Change -13 Rating 1,351

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.

April 2026 No new matches Change +2 Rating 1,364

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.

March 2026 No new matches Change +5 Rating 1,362

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.

February 2026 6 new matches · 8 left period Change -28 Rating 1,357

Rating-period composition

Rating matches
17 -2
Record
8–9 Previous month 9–10
Opponents
13 -1
Events
3 0

8 older matches left the 12-month period: 3 won and 5 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
February 21, 2026 Karen Avahimian
TATAMY 19: Czech Open Championship (kids) Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
Method Points 04:00 2–3
Marginal influence -10
Win
February 21, 2026 Alex Burďuch
TATAMY 19: Czech Open Championship (kids) Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
Method Submission 03:42 3–0
Marginal influence +10
Loss
February 21, 2026 Leon Fathi Kamari
TATAMY 19: Czech Open Championship (kids) Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
Method Submission 01:49 0–0
Marginal influence -9
Loss
February 21, 2026 Leon Fathi Kamari
TATAMY 19: Czech Open Championship (kids) Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
Method Submission 03:05 0–0
Marginal influence -10
Loss
February 21, 2026 Karen Avahimian
TATAMY 19: Czech Open Championship (kids) Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
Method Points 04:00 2–10
Marginal influence -7
Win
February 21, 2026 Matvei Golyashev
TATAMY 19: Czech Open Championship (kids) Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
Method Submission 03:02 12–2
Marginal influence +8
January 2026 5 new matches Change +66 Rating 1,385

Rating-period composition

Rating matches
19 +5
Record
9–10 Previous month 5–9
Opponents
14 +3
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.
Win
January 24, 2026 Unknown opponent
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) Gi / 10-12 years / Boy / -40 kg / Beginner
Method Points 04:00 16–2
Marginal influence +17
Loss
January 24, 2026 Karen Avahimian
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) Gi / 10-12 years / Boy / -40 kg / Beginner
Method Submission 03:15 2–0
Marginal influence -7
Win
January 24, 2026 Přemysl Černošek
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) Gi / 10-12 years / Boy / -40 kg / Beginner
Method Submission 02:11 9–0
Marginal influence +9
Win
January 24, 2026 Lukas Trnka
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) No-Gi / 10-12 years / Boy / -40 kg / Beginners
Method Submission 00:21 0–0
Marginal influence +11
Win
January 24, 2026 Karen Avahimian
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) No-Gi / 10-12 years / Boy / -40 kg / Beginners
Method Decision 04:00 0–0
Marginal influence +12
December 2025 No new matches Change +5 Rating 1,319

Rating-period composition

Rating matches
14 0
Record
5–9 Previous month 5–9
Opponents
11 0
Events
2 0

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

November 2025 6 new matches Change +3 Rating 1,314

Rating-period composition

Rating matches
14 +6
Record
5–9 Previous month 3–5
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
November 1, 2025 Eldar Sumoniuk
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
Method Submission 01:42 0–0
Marginal influence -18
Win
November 1, 2025 Volodymyr Demchuk
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
Method Submission 00:47 0–0
Marginal influence +12
Loss
November 1, 2025 Artem Pashetnykh
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
Method Decision 04:00 0–0
Marginal influence -12
Loss
November 1, 2025 David Mařík
TATAMY 17 KIDS (No-GI and GI round robin) Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
Method Points 04:00 2–7
Marginal influence -9
Win
November 1, 2025 Makar Datsenko
TATAMY 17 KIDS (No-GI and GI round robin) Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
Method Submission 02:16 2–0
Marginal influence +11
Loss
November 1, 2025 Zubayr Tsikhesashev
TATAMY 17 KIDS (No-GI and GI round robin) Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
Method Submission 01:33 0–0
Marginal influence -2
October 2025 No new matches · 1 left period Change -31 Rating 1,311

Rating-period composition

Rating matches
8 -1
Record
3–5 Previous month 4–5
Opponents
6 -1
Events
1 -1

1 older matches left the 12-month period: 1 won and 0 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

September 2025 No new matches Change +8 Rating 1,342

Rating-period composition

Rating matches
9 0
Record
4–5 Previous month 4–5
Opponents
7 0
Events
2 0

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

Relevant matches
12.2
Official ranking percentile
Top 43%
Performance
0.8 pp above expectation

12.2 weighted matches against 13 different opponents across 3 events

Weighted win rate
49.3%
Expected win rate
48.4%
Average opponent rating
1,343
Repeated-opponent share
23.5%
Network connectivity
80.9%

Classification evidence

Why U14?

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

  • U14 2 event votes Selected outcome

Registrations and outcomes

TATAMY 19: Czech Open Championship (kids)
U14 · Counts
Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
  • Competition age 12
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Competition age 12
GRIND 12 Kids (NO-GI & GI ROUND ROBIN)
U14 · Counts
No-Gi / 10-12 years / Boy / -40 kg / Beginners
  • Competition age 12
Gi / 10-12 years / Boy / -40 kg / Beginner
  • Competition age 12
TATAMY 18 KIDS (No-GI and GI round robin)
Does not count
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Competition age 11
Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
  • Competition age 11
TATAMY 17 KIDS (No-GI and GI round robin)
Does not count
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Competition age 11
Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
  • Competition age 11

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 3 competition events Selected outcome

Registrations and outcomes

TATAMY 19: Czech Open Championship (kids)
≤ 40 kg · Counts as a competition event
Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

3 matches in the rating period

TATAMY 19: Czech Open Championship (kids)
≤ 40 kg · Counts as a competition event
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

3 matches in the rating period

GRIND 12 Kids (NO-GI & GI ROUND ROBIN)
≤ 40 kg · Counts as a competition event
No-Gi / 10-12 years / Boy / -40 kg / Beginners
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

2 matches in the rating period

GRIND 12 Kids (NO-GI & GI ROUND ROBIN)
≤ 40 kg · Counts as a competition event
Gi / 10-12 years / Boy / -40 kg / Beginner
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

3 matches in the rating period

TATAMY 18 KIDS (No-GI and GI round robin)
Does not count
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

No matches in the rating period · no valid weight evidence

TATAMY 18 KIDS (No-GI and GI round robin)
Does not count
Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

No matches in the rating period · no valid weight evidence

TATAMY 17 KIDS (No-GI and GI round robin)
≤ 40 kg · Counts as a competition event
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

3 matches in the rating period

TATAMY 17 KIDS (No-GI and GI round robin)
≤ 40 kg · Counts as a competition event
Kids / No Gi / 10-12 years / Boys / Beginner / -40 kg
  • Registered weight class: -40 kg
  • Source competition limit: -40 kg

3 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 6 matches in the rating period Selected outcome

Registrations and outcomes

TATAMY 19: Czech Open Championship (kids)
grey · Counts as a match
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Source belt category: grey

3 matches in the rating period

TATAMY 17 KIDS (No-GI and GI round robin)
grey · Counts as a match
Kids / Gi / 10-12 years / Boys / White/grey belt / -40 kg
  • Source belt category: grey

3 matches in the rating period