| ITF M15 Antalya | 11/04 09:30 | - | John H Lithen vs Nicholas David Ionel | View | 
| ITF M15 Bol | 10/31 09:00 | - | [386] Andrej Nedic v Nicholas David Ionel [461] | 6-3,6-0 | |
| ITF M15 Bol | 10/30 09:00 | - | Nicholas David Ionel v Giuseppe La Vela | 6-7,7-6,6-1 | |
| ITF M15 Bol | 10/29 07:57 | - | Nicholas David Ionel v Lorenzo Comino | 3-6,6-2,6-2 | |
| ITF M15 Bol | 10/28 11:40 | - | Nicholas David Ionel v Kristian Tumbas Kajgo | 6-0,7-5 | |
| ITF M15 Bol | 10/23 10:52 | - | Nicholas David Ionel v Bohemios U23 | 5-7,3-6 | |
| ITF M15 Bol | 10/22 10:48 | - | Nicholas David Ionel v Anes Latifovic | 6-2,6-0 | |
| ITF M15 Otopeni | 09/25 09:00 | - | Nicholas David Ionel v Niklas Guttau | 4-6,6-1,4-6 | |
| ITF M15 Otopeni | 09/24 10:09 | - | Nicholas David Ionel v Mihai Alexandru Coman | 6-2,6-3 | |
| Challenger Targu Mures | 09/17 11:35 | 25 | 
                [424]                Nicholas David Ionel                v
                Daniel Rincon
                [209]                 
               | 
            0-6,2-6 | |
| Challenger Targu Mures | 09/08 14:30 | 25 | 
                 
                [406]                Mili Poljicak
                v
                Nicholas David Ionel                [396]               | 
            4-6,6-3,6-4 | |
| ITF M15 Buzau | 09/01 11:32 | - | Nicholas David Ionel v Edouard Villoslada | 1-6,5-7 | |
| ITF M15 Curtea de Arges | 08/08 10:45 | - | 
                                Nicholas David Ionel                v
                Hitchin
                                 
               | 
            4-6,3-6 | 
Nicholas David Ionel (born 12 October 2002) is a Romanian professional tennis player. He has a career high ATP singles ranking of No. 184 achieved on 12 June 2023 and a career high ATP doubles ranking of No. 356 achieved on 24 April 2023. He is currently the No. 4 Romanian player. Ionel won the 2020 Australian Open Junior doubles title with Leandro Riedi.
Ionel was awarded with a qualification wildcard to play his first ATP tournament at the 2020 European Open, where he pushed former world No. 36 Yūichi Sugita to three sets.
He reached the top 250 in singles on 7 November 2022 at No. 241.