| UTR Pro Tennis Series Hillerod | 02/20 09:00 | - | 페레즈 산즈, 다비드 v Nielsen, Frederik | 6-7,2-6 | |
| UTR Pro Tennis Series Hillerod | 02/19 09:02 | - | 라오렌트, 야나이스 v Nielsen, Frederik | 6-7,6-3,5-6 | |
| UTR Pro Tennis Series Hillerod | 02/18 12:30 | - | Jurriaan Bol v Nielsen, Frederik | 5-7,7-6,3-5 | |
| UTR Pro Tennis Series Hillerod | 02/17 14:05 | - | Alexander Stage v Nielsen, Frederik | 3-6,1-5 | |
| UTR Pro Tennis Series Hillerod | 02/16 15:00 | - | Sergio Redondo v Nielsen, Frederik | 0-6,1-6 | |
| UTR Pro Tennis Series Hillerod | 02/14 11:00 | - | 차호우드, 케빈 v Nielsen, Frederik | 6-4,6-7,0-6 | |
| ATP Doha | 03/06 09:00 | 64 | [58] Nielsen, Frederik v 라마나단, 람쿠마르 [202] | 4-6,1-6 | |
| Exo Tennis Germany Series | 07/18 11:35 | - | 모티어, 세바스티안 v Nielsen, Frederik | 4-6,3-6 | |
| Exo Tennis Germany Series | 07/17 09:25 | - | [474] 판세로, 세바스티안 v Nielsen, Frederik [55] | 6-3,6-7,2-6 | |
| Exo Tennis Germany Series | 07/16 11:45 | - | Fritsche, Dominik v Nielsen, Frederik | 1-6,2-6 | |
| Exo Tennis Germany Series | 07/15 14:05 | - | Penzlin, Julien v Nielsen, Frederik | 2-6,1-6 | |
| Exo Tennis Germany Series | 07/14 09:50 | - | Worn, Julian v Nielsen, Frederik | 3-6,1-6 | |
| 파이널, 플레이오프 | 03/07 12:40 | 45 | Nielsen, Frederik v 가르시아, 이그나시오 | 7-6,6-2 | |
| New York, USA | 02/09 20:30 | 64 | [110] 소에다, 고 v Nielsen, Frederik [54] | 6-1,6-2 | |
| Challenger Phoenix | 03/13 18:40 | 24 | [484] Nielsen, Frederik v 폴란스키, 페터 [127] | 6-7,3-6 | |
| Challenger Phoenix | 03/11 17:00 | 166 | [484] Nielsen, Frederik v Martin, Fabrice [77] | 6-4,7-6 | |
| Challenger Noumea | 12/31 04:05 | 24 | [348] 마주어, 다니엘 v Nielsen, Frederik [58] | 6-1,5-7,6-4 | |
| Challenger Fairfield | 10/08 17:00 | 54 | [295] 킹, 케빈 v Nielsen, Frederik [66] | 6-4,6-3 | |
| Challenger Fairfield | 10/07 18:15 | 46 | [334] 키아트코우스키, 다이손 v Nielsen, Frederik [69] | 7-6,3-6,5-7 | |
| Challenger Fairfield | 10/06 22:15 | 45 | [69] Nielsen, Frederik v 오르테가-올메도, 로베르토 [316] | 6-2,6-2 | |
| Challenger Stockton | 09/29 23:05 | 45 | [466] 리츠찰드, 알렉산더 v Nielsen, Frederik [68] | 6-4,7-6 | |
| Challenger Tiburon | 09/22 18:15 | 45 | [68] Nielsen, Frederik v 사르키시안, 알렉산더 [340] | 4-6,5-7 | |
| Challenger Cary | 09/08 18:20 | 45 | [67] Nielsen, Frederik v 송, 에반 [402] | 2-6,6-7 | |
| Challenger Chicago | 09/02 22:00 | 46 | [299] 우치다, 카이치 v Nielsen, Frederik [67] | 6-3,6-4 | |
| Challenger Chicago | 09/02 15:00 | 45 | [391] de Loore, Joris v Nielsen, Frederik [67] | 6-7,6-2,5-7 | |
| Portoroz, Slovenia | 08/07 08:00 | 25 | [226] 미에들러, 루카스 v Nielsen, Frederik [64] | 6-3,6-2 | |
| Challenger Portoroz Qual | 08/06 08:00 | 54 | [64] Nielsen, Frederik v 올리베티, 알바노 [318] | 6-2,7-6 | |
| Challenger Portoroz Qual | 08/05 08:00 | 46 | [333] 펠레그리노, 안드레아 v Nielsen, Frederik [63] | 0-6,0-6 | |
| Challenger Portoroz Qual | 08/04 09:35 | 45 | Nielsen, Frederik v Dimic, Matic | 7-5,6-0 | |
| Challenger Segovia Qual | 07/29 14:30 | 46 | [351] 마모운, 카림-모하메드 v Nielsen, Frederik [65] | 7-6,3-6,6-2 |