| Challenger - Girona | 03/26 10:00 | 14 | [345] Nikolas S Izquierdo v Steven Diez [282] | 3-6,4-6 | |
| Challenger - Las Franquesas del Vallés | 03/21 15:00 | 25 | [345] Nikolas S Izquierdo v Hugo Grenier [146] | 4-6,4-6 | |
| Challenger - Székesfehérvár | 03/14 14:10 | 25 | [295] Nikolas S Izquierdo v Alessandro Giannessi [235] | 4-6,7-6,4-6 | |
| Challenger - Antália | 03/07 10:05 | 25 | [342] Salvatore Caruso v Nikolas S Izquierdo [295] | 6-7,6-4,6-2 | |
| ITF - M25 Torelló | 03/03 09:25 | 27 | [486] John Echeverria v Nikolas S Izquierdo [288] | 6-3,6-4 | |
| ITF - M25 Torelló | 03/02 12:25 | 26 | Diego A B Sanchez v Nikolas S Izquierdo | 6-7,3-6 | |
| ITF - M25 Torelló | 03/01 09:00 | 25 | Daniele Capecchi v Nikolas S Izquierdo | 2-6,1-6 | |
| Challenger - Cherbourg | 02/15 09:00 | 25 | [285] Nikolas S Izquierdo v Joris De Loore [206] | 2-6,6-7 | |
| Challenger - Tenerife | 01/29 10:00 | 14 | [270] Nikolas S Izquierdo v Alvaro Lopez San Martin [384] | 5-7,6-7 | |
| ITF - M25 Manacor | 01/27 13:00 | 27 | [270] Nikolas S Izquierdo v Daniel Rincon [427] | 4-6,1-6 | |
| ITF - M25 Manacor | 01/26 11:00 | 26 | Nikolas S Izquierdo v Xavi Matas Ortega | 6-1,6-3 | |
| ITF - M25 Manacor | 01/25 14:10 | 25 | Nikolas S Izquierdo v Imanol L Morillo | 6-7,6-2,7-6 | |
| Challenger - Tenerife | 01/17 14:55 | 25 | [270] Nikolas S Izquierdo v Francesco Passaro [120] | 1-6,4-6 | |
| Challenger - Oeiras | 01/10 12:15 | 25 | [270] Nikolas S Izquierdo v Pedro Sousa [494] | 6-7,3-6 | |
| Challenger - Maspalomas | 11/29 14:40 | 25 | [258] Nikolas S Izquierdo v Oriol Roca Batalla [299] | 2-6,4-6 | |
| Challenger - Valência | 11/23 10:30 | 26 | [263] Nikolas S Izquierdo v Nikola Milojevic [259] | 7-5,3-6,4-6 | |
| Challenger - Valência | 11/22 09:00 | 25 | [268] Alessandro Giannessi v Nikolas S Izquierdo [263] | 2-6,4-6 | |
| Challenger - Valência | 11/22 09:00 | 25 | Bernabe Zapata Miralles v Nikolas S Izquierdo | Cancelled | |
| Challenger - Roanne | 11/10 11:40 | 26 | [210] Luca Van Assche v Nikolas S Izquierdo [267] | 6-3,6-3 | |
| Challenger - Roanne | 11/09 12:40 | 25 | [212] Jay Clarke v Nikolas S Izquierdo [267] | 3-6,6-1,2-6 | |
| Challenger - Guaiaquil | 11/02 15:00 | 25 | [263] Nikolas S Izquierdo v Matheus P De Almeida [214] | 1-6,6-7 | |
| ATP - Gijón | 10/09 12:00 | 19 | [147] Manuel Guinard v Nikolas S Izquierdo [275] | 4-6,7-5,7-5 | |
| ATP - Gijón | 10/08 17:05 | 14 | [336] Johan Nikles v Nikolas S Izquierdo [275] | 2-6,6-1,1-6 | |
| Challenger - Parma | 10/05 14:35 | 26 | [275] Nikolas S Izquierdo v Dusan Lajovic [85] | 1-6,3-6 | |
| Challenger - Parma | 10/03 11:35 | 25 | [275] Nikolas S Izquierdo v Nicholas D Ionel [256] | 6-3,6-1 | |
| Challenger - Lisboa | 09/25 10:25 | 14 | [238] Nikolas S Izquierdo v Pedro Araujo [444] | Retired | |
| Challenger - Braga | 09/21 10:00 | 26 | [238] Nikolas S Izquierdo v Carlos Taberner [121] | 2-6,4-6 | |
| Challenger - Braga | 09/20 14:15 | 25 | [251] Frederico Ferreira Silva v Nikolas S Izquierdo [238] | 2-6,5-7 | |
| Challenger - Szczecin | 09/13 11:00 | 25 | [241] Nikolas S Izquierdo v Corentin Moutet [84] | 5-7,6-0,4-6 | |
| Challenge - Sevilha | 09/07 15:30 | 26 | [257] Nikolas S Izquierdo v Federico Delbonis [134] | 3-6,2-6 |
Nikolás Sánchez Izquierdo (born 17 March 1999) is a Spanish tennis player.
Sánchez Izquierdo has a career high ATP singles ranking of 238 achieved on 19 September 2022 and a career high ATP doubles ranking of 562 achieved on 29 November 2021.