Marin, Oscar
Current rating: 1516
Record: 4-3
| Grand Prix Costa Rica 2012 (M13 limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 19 | Rivera Azofeifa, Jose (1500) | Won 2-1 | +181518 |
| 3sealed | 65 | Guerra Guzman, Alfonso (1518) | Lost 0-2 | -181500 |
| 4sealed | 149 | Jimenez Ruiz, Luis David (1464) | Won 2-0 | +171517 |
| 5sealed | 106 | Barreto, Ricardo (1518) | Won 2-1 | +181535 |
| 6sealed | 93 | Cordon, Diego (1500) | Won 2-1 | +181553 |
| 7sealed | 46 | Schwartz, Stephen (1533) | Lost 0-2 | -191534 |
| 8sealed | 59 | Calvo, Javier (1535) | Lost 0-2 | -181516 |
| average opponent: 1510record: 4-3 | new rating: 1516 | |||