| 2026-02-17 | Doha | Hard | R32 | 17 |  Karen Khachanov (7) | 117 |  Shintaro Mochizuki | 6-1 3-6 6-4 | H2H | 3 | 115 | 7 | 2 | 62.2% | 76.1% | 42.9% | 2/5 |
| 2026-02-06 | Davis Cup QLS R1: JPN vs AUT | Hard | RR | 170 |  Jurij Rodionov | 108 | Shintaro Mochizuki | 6-4 7-5 | H2H | 3 | 108 | 7 | 4 | 49.4% | 76.3% | 46.2% | 7/9 |
| 2026-02-06 | Davis Cup QLS R1: JPN vs AUT | Hard | RR | 223 | Lukas Neumayer | 108 | Shintaro Mochizuki | 6-3 6-3 | H2H | 3 | 75 | 3 | 1 | 61.2% | 86.7% | 63.2% | 2/2 |
| 2026-01-20 | Australian Open | Hard | R128 | 35 |  Stefanos Tsitsipas (31) | 112 | Shintaro Mochizuki | 4-6 6-3 6-2 6-2 | H2H | 5 | 180 | 16 | 6 | 68.6% | 79.2% | 48.5% | 7/8 |
| 2026-01-04 | United Cup | Hard | RR | 128 |  Billy Harris | 99 | Shintaro Mochizuki | 7-6(4) 6-3 | H2H | 3 | 110 | 4 | 3 | 58.6% | 73.2% | 55.2% | 4/6 |
| 2026-01-02 | United Cup | Hard | RR | 36 | Stefanos Tsitsipas | 99 | Shintaro Mochizuki | 6-3 6-4 | H2H | 3 | 82 | 8 | 2 | 68.9% | 66.7% | 57.9% | 1/2 |
| 2025-10-13 | Almaty | Hard | QF | 36 |  Alex Michelsen (6) | 102 | Shintaro Mochizuki | 6-3 3-6 6-2 | H2H | 3 | 124 | 12 | 2 | 68.3% | 71.0% | 34.4% | 6/9 |
| 2025-10-13 | Almaty | Hard | R16 | 102 | Shintaro Mochizuki | 26 |  Luciano Darderi (4) | 6-3 6-3 | H2H | 3 | 64 | 9 | 1 | 51.1% | 82.6% | 63.6% | 0/1 |
| 2025-10-13 | Almaty | Hard | R32 | 102 | Shintaro Mochizuki | 58 |  Arthur Cazaux | 6-4 6-4 | H2H | 3 | 89 | 3 | 4 | 51.6% | 78.8% | 61.3% | 2/2 |
| 2025-09-24 | Tokyo | Hard | R32 | 12 |  Casper Ruud (4) | 106 | Shintaro Mochizuki | 4-6 6-1 6-1 | H2H | 3 | 99 | 10 | 2 | 76.2% | 81.3% | 26.7% | 4/6 |
