CChessStats

I Abierto Guanacasteco Santa Cruz 2026

Open SwissStandard

24 players participated in this 7-round tournament, held from 09 May 2026 to 10 May 2026 in Centro Civico por La Paz, Santa Cruz, Costa Rica. Top 10 Elo average was 1586, and top seed was Paul Usselman (🇨🇦 CAN, 1818).

Sebastian Castillo Chavarria (🇨🇷 CRC, 1701) won with 6.0/7, ahead of Jackson Robert Cosman (5.5) and Myckel Navarrete Badilla (5.0). Castillo Chavarria shared the lead from round 5 and won solo starting round 6.

The biggest upset came in round 6: Jackson Robert Cosman (1610) beat Paul Usselman (1818), a +208-point gap.

Location
🇨🇷Centro Civico por La Paz, Santa Cruz, Costa Rica
Dates
09 May 2026 → 10 May 2026
Time control
Standard: 30 minutes for game with 30 seconds increment from move 1
System
Swiss · 7 rounds
Avg top 10
1,586
Participants
24
Federations · 1 represented
🇨🇷Costa Rica×15
Top 3

How it unfolded

Top 6 · 7 rounds

Sebastian Castillo Chavarria led from R6; +0.5-point edge over the runner-up.

Co-leaders
15
6
3
1
2
1
1
23.55.57R1R2R3R4R5R6R7Castillo Chavarria takes lead
Castillo Chavarria6Cosman5.5Rojas Barrantes5Navarrete Badilla5Rodriguez Castillo5Pomares Zuniga4.5
R6 · LEADER CHANGE10 May

Sebastian Castillo Chavarria takes the sole lead (5.5/6).

R7 · HEAD-TO-HEAD · WINNER VS 2ND

Sebastian Castillo Chavarria drew with Jackson Robert Cosman (Black).

WIN STREAKS · 2 top finishers

Sebastian Castillo Chavarria 3 wins (R1–R3)Jackson Robert Cosman 3 wins (R4–R6)

Key matchups · top 4

Head-to-head between the four finishers
Player1234
1Sebastian Castillo Chavarria*
½
——
2Jackson Robert Cosman
½
*—
1
3Rad el Rojas Barrantes——*
½
4Myckel Navarrete Badilla—
0
½
*

Grille américaine

#PlayerEloFedR1R2R3R4R5R6R7PtsBu C1BuSBPerfΔ
1Castillo Chavarria, Sebastian1701CRC+20B+6N+8B=?N+4B+?B=2N6.021.021.018.251898+15.4
2Cosman, Jackson Robert1610CRC+24B+3B−?N+16N+6B+?N=1B5.520.020.017.001903+50.8
3Navarrete Badilla, Myckel1663CRC+16B−2N+17B+11N+9N=5B=?B5.024.524.516.501641-2.0
4Rodriguez Castillo, Gerardo1626CRC−18N+13B+19N+12B−1N+11B+?N5.023.523.514.501600-2.8
5Rojas Barrantes, Rad el1647CRC+21B=17N+10B−?B+7N=3N+8B5.022.522.518.501911+44.4
6Rosales Garcia, Alex Alfredo1475CRC+22N−1B+21N=7B−2N+13B+14N4.525.027.013.251360-15.2
7Pomares Zuniga, Noel Lazaro1588CRC+15B+9N−?B=6N−5B+16N+10B4.524.024.016.751611+4.8
8Pomares Herrera, Efrain1537CRC+14N+18B−1N−9B+19N+12B−5N4.025.528.513.50874-12.6
9Espinoza Rosales, Marco Antonio0CRC+?B−7B+18N+8N−3B−10N+17B4.023.523.510.0013820.0
10Jimenez Noguera, Matias1513CRC−13N+14B−5N+24B+21N+9B−7N4.022.524.011.00818-28.8
11Lara Moreno, Jose Adrian1499CRC+23B−?N+20B−3B+18N−4N+19B4.020.020.010.00845-24.4
12Rodriguez Porras, Rosa0CRC+?B−?N+15B−4N+16B−8N+?B4.015.515.56.5014060.0
13FIDE 65807500—+10B−4N−16B=15N+20B−6N+?N3.522.022.07.7513180.0
14FIDE 65807770—−8B−10N+?B+20N=17B+15N−6B3.521.021.07.007080.0
15FIDE 65763620—−7N+?B−12N=13B+?N−14B+21N3.517.517.53.757880.0
16Vargas Hernandez, Anthony Matias1429CRC−3N+24B+13N−2B−12N−7B+22N3.024.526.07.00820-30.4
17Villegas Villalobos, Oscar0CRC+?N=5B−3N−19B=14N+18B−9N3.023.523.57.2514620.0
18Badilla Junez, Adrian Antonio0CRC+4B−8N−9B+?N−11B−17N+20B3.022.022.07.0014290.0
19FIDE 65661540—−?B+23N−4B+17N−8B+?N−11N3.018.018.05.007540.0
20FIDE 65709760—−1N+22B−11N−14B−13N+?B−18N2.022.022.02.008000.0
21FIDE 65806450—−5N+?B−6B+?N−10B−?N−15B2.017.017.00.007450.0
22FIDE 65807850—−6B−20N=?N−23B+?N=24B−16B2.013.013.00.756520.0
23FIDE 65807690—−11N−19B−?N+22N−?B−?B+?N2.09.09.02.006990.0
24FIDE 65808230—−2N−16N+?B−10N−?B=22N−?B1.514.514.51.007170.0

Key insights

Biggest movers and upsets — the story behind the numbers.

Top rating gainers
Top rating losers
Biggest upsets