| ITF M25 Martos | 06/19 11:00 | 25 | Sergi Perez Contri v Mertens, Yannick | 2-6,2-6 | |
| ITF M25 Jablonec Nad Nisou | 05/21 11:40 | 25 | [397] Bangoura, Sekou v Mertens, Yannick [435] | 6-4,6-0 | |
| Challenger - Aix en Provence | 05/06 15:00 | 24 | [252] Troicki, Viktor v Mertens, Yannick [431] | 6-3,6-1 | |
| Challenger - Bordeaux | 04/29 12:55 | 24 | [429] Mertens, Yannick v Calvin Hemery [317] | 2-6,2-6 | |
| ITF - M25 Sunderland | 04/12 11:30 | 27 | [423] Igor Sijsling v Mertens, Yannick [428] | 6-2,6-4 | |
| ITF - M25 Sunderland | 04/11 11:05 | 26 | [428] Mertens, Yannick v Gijs Brouwer [415] | 7-5,6-2 | |
| ITF - M25 Sunderland | 04/09 11:35 | 25 | Alexis Canter v Mertens, Yannick | 2-6,6-7 | |
| Bolton, Qualifications Simples M-ITF-GBR-03A | 04/02 09:00 | 25 | [490] Hoyt, Evan v Mertens, Yannick [429] | 6-3,6-3 | |
| Challenger St Brieuc | 03/25 09:00 | 166 | [127] Stakhovsky, Sergiy v Mertens, Yannick [441] | 6-3,6-4 | |
| Challenger - Lille | 03/20 15:50 | 25 | [120] Gregoire Barrere v Mertens, Yannick [441] | 6-4,6-1 | |
| Challenger - Lille | 03/19 09:00 | 24 | [441] Mertens, Yannick v Evan Furness [420] | 6-0,7-6 | |
| Challenger - Lille | 03/18 09:00 | 166 | [421] Artunedo Martinav. v Mertens, Yannick [454] | 4-6,4-6 | |
| Drummondville, Canada | 03/13 17:20 | 25 | [454] Mertens, Yannick v Kaichi Uchida [282] | 5-7,6-4,4-6 | |
| Drummondville, Canada | 03/12 14:00 | 24 | [333] Matias Franco Descotte v Mertens, Yannick [454] | 2-6,7-6,1-6 | |
| ITF - M25 Trente | 02/28 10:00 | 26 | [454] Mertens, Yannick v Lenz, Julian [395] | 3-6,4-6 | |
| ITF - M25 Trente | 02/27 11:00 | 25 | Mertens, Yannick v Frigerio, Lorenzo | 3-6,7-6,7-5 | |
| ITF M25 Glasgow | 02/19 10:00 | 25 | [451] Mertens, Yannick v van Rijthoven, Tim [450] | 3-6,2-6 | |
| ITF - M15 Grenoble | 02/10 14:30 | 29 | Mitjana, Leny v Mertens, Yannick | 6-3,7-5 | |
| ITF - M15 Grenoble | 02/09 14:30 | 28 | Matteo Martineau v Mertens, Yannick | 3-6,4-6 | |
| ITF - M15 Grenoble | 02/08 10:00 | 27 | Yanais Laurent v Mertens, Yannick | 3-6,3-6 | |
| ITF - M15 Grenoble | 02/07 11:40 | 26 | Ugo Blanchet v Mertens, Yannick | 6-3,4-6,4-6 | |
| ITF - M15 Grenoble | 02/06 10:00 | 25 | Bernabe, Arthur v Mertens, Yannick | 1-6,0-6 | |
| ITF - M15 Sharm El Sheikh | 01/31 09:45 | 26 | Mertens, Yannick v Vivero Gonzalez, Pablo | 2-6,6-4,2-6 | |
| ITF - M15 Sharm El Sheikh | 01/30 12:15 | 25 | [457] Mertens, Yannick v Yu Hsiou Hsu [307] | 6-3,6-0 | |
| Challenger Rennes | 01/24 15:35 | 26 | [111] Elias Ymer v Mertens, Yannick [410] | 6-3,6-4 | |
| Challenger Rennes | 01/23 17:05 | 25 | [269] Evgeny Karlovskiy v Mertens, Yannick [410] | 3-6,6-7 | |
| Challenger Rennes | 01/21 09:00 | 166 | [455] Jacq, Gregoire v Mertens, Yannick [410] | 7-5,6-2 | |
| ITF - M15 Bressuire | 01/18 13:00 | 27 | Mertens, Yannick v Mitjana, Leny | 6-7,5-7 | |
| ITF - M15 Bressuire | 01/17 11:00 | 26 | [466] Heyman, Christopher v Mertens, Yannick [410] | 3-6,0-6 | |
| ITF - M15 Bressuire | 01/16 09:00 | 25 | Clement Tabur v Mertens, Yannick | 2-6,3-6 |