| 3 mar 2021 | Sanchez Vigon, David (Sazed21) | Ver la partida 0-1 | -Dommaraju, Gukesh (GukeshDomma | B13 Caro-Kann Defense: Exchange Variation | | ronda 4 · mesa 1 |
| 3 mar 2021 | Dommaraju, Gukesh (GukeshDomma | Ver la partida 1-0 | -Sanchez Vigon, David (Sazed21) | D02 Queen's Pawn Game: London System | | ronda 4 · mesa 2 |
| 3 mar 2021 | Hellinga Damstra, Martien (asturfriso | Ver la partida 0-1 | -Cascudo Pueyo, Ignacio (icasc) | C06 French Defense: Tarrasch Variation, Closed Variation, Main Line | | ronda 4 · mesa 3 |
| 3 mar 2021 | Cascudo Pueyo, Ignacio (icasc) | Ver la partida 1-0 | -Hellinga Damstra, Martien (asturfriso | B47 Sicilian Defense: Taimanov Variation, Bastrikov Variation | | ronda 4 · mesa 4 |
| 3 mar 2021 | Copena Rodriguez, Damian (Revirado) | Ver la partida 1-0 | -Alonso Alvarez, Aitor (SmaugFire) | B20 Sicilian Defense | Universidad de Oviedo A – Vetusta A | ronda 4 · mesa 5 |
| 3 mar 2021 | Alonso Alvarez, Aitor (SmaugFire) | Ver la partida 0-1 | -Copena Rodriguez, Damian (Revirado) | D02 Queen's Pawn Game: Symmetrical Variation, Pseudo-Catalan | Universidad de Oviedo A – Vetusta A | ronda 4 · mesa 6 |
| 3 mar 2021 | Martinez Lopez, Eduardo (Emlz) | Ver la partida 1-0 | -Gonzalez Gonzalez, Javier (Jgg2010) | B38 Sicilian Defense: Accelerated Dragon, Maróczy Bind | Antonio Rico A – Vetusta C | ronda 4 · mesa 7 |
| 3 mar 2021 | Gonzalez Gonzalez, Javier (Jgg2010) | Ver la partida 1-0 | -Martinez Lopez, Eduardo (Emlz) | E05 Catalan Opening: Open Defense, Classical Line | Antonio Rico A – Vetusta C | ronda 4 · mesa 8 |
| 3 mar 2021 | Adanez Navarro, Xabier (Xabi1) | Ver la partida 0-1 | -Blazquez Lopez, Berna (JAVIERAGUERA | B18 Caro-Kann Defense: Classical Variation | | ronda 4 · mesa 9 |
| 3 mar 2021 | Blazquez Lopez, Berna (JAVIERAGUERA | Ver la partida 1-0 | -Adanez Navarro, Xabier (Xabi1) | D53 Queen's Gambit Declined | | ronda 4 · mesa 10 |
| 3 mar 2021 | Fernandez Perez, Samuel (DNC1314) | Ver la partida 1-0 | -Junquera Guerrero, David (Davidjg4029) | B50 Sicilian Defense: Modern Variations | Universidad de Oviedo B – Grupo 64 | ronda 4 · mesa 11 |
| 3 mar 2021 | Junquera Guerrero, David (Davidjg4029) | Ver la partida 0-1 | -Fernandez Perez, Samuel (DNC1314) | C50 Italian Game | Universidad de Oviedo B – Grupo 64 | ronda 4 · mesa 12 |
| 3 mar 2021 | Mulet Durango, Carolina (CarolinaM | Ver la partida 0-1 | -Diaz Hevia, Nicolas (nico_dh) | A46 Indian Defense: Spielmann-Indian | | ronda 4 · mesa 13 |
| 3 mar 2021 | Diaz Hevia, Nicolas (nico_dh) | Ver la partida 1-0 | -Mulet Durango, Carolina (CarolinaM | A36 English Opening: Symmetrical Variation, Two Knights, Fianchetto Variation | | ronda 4 · mesa 14 |
| 3 mar 2021 | Alvarez De Diego, Eden (miperrosisto) | Ver la partida 1-0 | -Lopez Fernandez, Marcos (MarcosLfdz) | C54 Italian Game: Classical Variation, Giuoco Pianissimo | Antonio Rico B – Antonio Rico C | ronda 4 · mesa 15 |
| 3 mar 2021 | Lopez Fernandez, Marcos (MarcosLfdz) | Ver la partida 1-0 | -Alvarez De Diego, Eden (miperrosisto) | C54 Italian Game: Classical Variation, Giuoco Pianissimo | Antonio Rico B – Antonio Rico C | ronda 4 · mesa 16 |
| 3 mar 2021 | Lorenzo Alvarez, Luis Emilio (luisel | Ver la partida 1-0 | -Torio Solis, Adrian (Adrian-Ts) | C50 Italian Game: Giuoco Pianissimo, Italian Four Knights Variation | | ronda 4 · mesa 17 |
| 3 mar 2021 | Torio Solis, Adrian (Adrian-Ts) | Ver la partida 0-1 | -Lorenzo Alvarez, Luis Emilio (luisel | C01 French Defense: Exchange Variation | | ronda 4 · mesa 18 |
| 3 mar 2021 | Badillo Ramos, Steve (miguelanguel | Ver la partida 0-1 | -Antuna Egocheaga, Rafael Eduardo (raf | B31 Sicilian Defense: Nyezhmetdinov-Rossolimo Attack, Fianchetto Variation | | ronda 4 · mesa 19 |
| 3 mar 2021 | Antuna Egocheaga, Rafael Eduardo (raf | Ver la partida 1-0 | -Badillo Ramos, Steve (miguelanguel | C02 French Defense: Advance Variation, Nimzowitsch Gambit | | ronda 4 · mesa 20 |
| 3 mar 2021 | Centron Antuna, Daniel (Dacean99) | Ver la partida ½-½ | -Alonso Fernandez, Gonzalo (GenioAlfa) | D02 Queen's Pawn Game: London System | Grupo Covadonga – Vetusta B | ronda 4 · mesa 21 |
| 3 mar 2021 | Alonso Fernandez, Gonzalo (GenioAlfa) | Ver la partida ½-½ | -Centron Antuna, Daniel (Dacean99) | B32 Sicilian Defense: Löwenthal Variation | Grupo Covadonga – Vetusta B | ronda 4 · mesa 22 |
| 3 mar 2021 | Alvarez Fernandez, Enrique (kinkaiser) | Ver la partida 1-0 | -Sierra Vallina, Lionel (Zenosama8) | A80 Dutch Defense | Gijon 64 – Ensidesa A | ronda 4 · mesa 23 |
| 3 mar 2021 | Sierra Vallina, Lionel (Zenosama8) | Ver la partida 0-1 | -Alvarez Fernandez, Enrique (kinkaiser) | A20 English Opening: King's English Variation | Gijon 64 – Ensidesa A | ronda 4 · mesa 24 |
| 3 mar 2021 | Fernandez Fernandez, Marcos (marcosff006 | Ver la partida 1-0 | -Alvarez Gonzalez, Alvaro (Negro_Azaba | C50 Italian Game: Giuoco Piano | | ronda 4 · mesa 25 |
| 3 mar 2021 | Alvarez Gonzalez, Alvaro (Negro_Azaba | Ver la partida 1-0 | -Fernandez Fernandez, Marcos (marcosff006 | C51 Italian Game: Evans Gambit, Anderssen Variation | | ronda 4 · mesa 26 |
| 3 mar 2021 | Gonzalez Guedes, Iyan (IyanBuho) | Ver la partida 1-0 | -De La Pena Garcia, Blanca (Blanca226) | B22 Sicilian Defense: Alapin Variation | | ronda 4 · mesa 27 |
| 3 mar 2021 | De La Pena Garcia, Blanca (Blanca226) | Ver la partida 0-1 | -Gonzalez Guedes, Iyan (IyanBuho) | A01 Nimzo-Larsen Attack: Indian Variation | | ronda 4 · mesa 28 |
| 3 mar 2021 | Antuna Pavon, Lucas (milucas2008) | Ver la partida 1-0 | -Varela Cano, Hugo (HugoChess_33) | B80 Sicilian Defense: Scheveningen Variation | Antonio Rico A – Vetusta C | ronda 4 · mesa 29 |
| 3 mar 2021 | Varela Cano, Hugo (HugoChess_33) | Ver la partida 1-0 | -Antuna Pavon, Lucas (milucas2008) | B45 Sicilian Defense: Four Knights Variation | Antonio Rico A – Vetusta C | ronda 4 · mesa 30 |
| 3 mar 2021 | Rodriguez Garcia, Jose Antonio (joanr | Ver la partida 1-0 | -De Martin Burtseva, Ivan (Ivan0411Ovied | D31 Queen's Gambit Declined: Queen's Knight Variation | | ronda 4 · mesa 31 |
| 3 mar 2021 | De Martin Burtseva, Ivan (Ivan0411Ovied | Ver la partida 0-1 | -Rodriguez Garcia, Jose Antonio (joanr | B21 Sicilian Defense: Smith-Morra Gambit Accepted | | ronda 4 · mesa 32 |
| 3 mar 2021 | Biempica Marin, Alvaro (ALBM2011) | Ver la partida 1-0 | -Fernandez Calvo, Martin (martin32fde | A45 Indian Defense | | ronda 4 · mesa 33 |
| 3 mar 2021 | Fernandez Calvo, Martin (martin32fde | Ver la partida ½-½ | -Biempica Marin, Alvaro (ALBM2011) | A22 English Opening: King's English Variation, Two Knights Variation | | ronda 4 · mesa 34 |
| 3 mar 2021 | Gonzalez Garcia, Jesus (chuxjanter) | Ver la partida 1-0 | -Fernandez Garcia, Daniel (DaniFernand | C54 Italian Game: Classical Variation, Giuoco Pianissimo | | ronda 4 · mesa 35 |
| 3 mar 2021 | Fernandez Garcia, Daniel (DaniFernand | Ver la partida 0-1 | -Gonzalez Garcia, Jesus (chuxjanter) | C00 French Defense: Knight Variation | | ronda 4 · mesa 36 |
| 3 mar 2021 | Fernandez Trancon, David (David_Tranco | Ver la partida 1-0 | -Arribas Castro, Mauro (Mauro_Gijon) | D02 Queen's Pawn Game: Chigorin Variation | | ronda 4 · mesa 37 |
| 3 mar 2021 | Arribas Castro, Mauro (Mauro_Gijon) | Ver la partida ½-½ | -Fernandez Trancon, David (David_Tranco | B10 Caro-Kann Defense | | ronda 4 · mesa 38 |
| 3 mar 2021 | Rodriguez San Jose, Daniel (DANIEL_CABA | Ver la partida 1-0 | -Corrales Fernandez, Raul (Raulcf28) | D02 Queen's Pawn Game: Chigorin Variation | | ronda 4 · mesa 39 |
| 3 mar 2021 | Corrales Fernandez, Raul (Raulcf28) | Ver la partida 0-1 | -Rodriguez San Jose, Daniel (DANIEL_CABA | C45 Scotch Game: Classical Variation | | ronda 4 · mesa 40 |
| 3 mar 2021 | Martinez Otero, Carlos (omc40) | Ver la partida ½-½ | -Del Valle Rosas, Alfonso (DELVALLEOF | D37 Queen's Gambit Declined: Three Knights Variation | | ronda 4 · mesa 41 |
| 3 mar 2021 | Del Valle Rosas, Alfonso (DELVALLEOF | Ver la partida 1-0 | -Martinez Otero, Carlos (omc40) | D00 Queen's Pawn Game: Accelerated London System | | ronda 4 · mesa 42 |
| 3 mar 2021 | Suarez Montousse, Andres (andresmonto | Ver la partida 0-1 | -Ortiz Fernandez De La Vega, Alejandro Manuel (s | A45 Trompowsky Attack | | ronda 4 · mesa 43 |
| 3 mar 2021 | Ortiz Fernandez De La Vega, Alejandro Manuel (s | Ver la partida 1-0 | -Suarez Montousse, Andres (andresmonto | B06 Modern Defense | | ronda 4 · mesa 44 |
| 3 mar 2021 | Suarez Prendes, Rufino (pezapo) | Ver la partida 0-1 | -Baragano Campa, David (ebwjes) | C02 French Defense: Advance Variation, Milner-Barry Gambit, Main Line | Valdesva – Ciudad Naranco A | ronda 4 · mesa 45 |
| 3 mar 2021 | Baragano Campa, David (ebwjes) | Ver la partida 1-0 | -Suarez Prendes, Rufino (pezapo) | B03 Alekhine Defense: Exchange Variation | Valdesva – Ciudad Naranco A | ronda 4 · mesa 46 |
| 3 mar 2021 | Gonzalez Menendez, Ivan (StarkAst) | Ver la partida 1-0 | -Bazan Solera, Manuel (bazan55) | B07 Pirc Defense: Byrne Variation | Universidad de Oviedo A – Vetusta A | ronda 4 · mesa 47 |
| 3 mar 2021 | Bazan Solera, Manuel (bazan55) | Ver la partida 0-1 | -Gonzalez Menendez, Ivan (StarkAst) | A00 Hungarian Opening | Universidad de Oviedo A – Vetusta A | ronda 4 · mesa 48 |
| 3 mar 2021 | Arias Torio, Sergio (Torpinson) | Ver la partida ½-½ | -Garcia Cueva, Miguel (Megamiguelm | D14 Slav Defense: Exchange Variation, Symmetrical Line | | ronda 4 · mesa 49 |
| 3 mar 2021 | Garcia Cueva, Miguel (Megamiguelm | Ver la partida 0-1 | -Arias Torio, Sergio (Torpinson) | B35 Sicilian Defense: Accelerated Dragon, Modern Bc4 Variation | | ronda 4 · mesa 50 |