| 2021-11-28 | Davis Cup Finals RR: GER vs AUT | Hard | RR | 51 |  Jan-Lennard Struff | 118 |  Dennis Novak | 7-5 6-4 | H2H | 3 | 72 | 7 | 0 | 68.3% | 70.7% | 68.4% | 0/1 |
| 2021-11-26 | Davis Cup Finals RR: SRB vs AUT | Hard | RR | 1 |  Novak Djokovic | 118 | Dennis Novak | 6-3 6-2 | H2H | 3 | 57 | 3 | 0 | 61.9% | 84.6% | 87.5% | 0/0 |
| 2021-10-25 | Vienna | Hard | R16 | 11 |  Jannik Sinner (7) | 116 | Dennis Novak (WC) | 6-4 6-2 | H2H | 3 | 76 | 2 | 3 | 62.7% | 75.7% | 54.5% | 6/6 |
| 2021-10-25 | Vienna | Hard | R32 | 116 | Dennis Novak (WC) | 68 | Gianluca Mager (Q) | 7-6(4) 7-6(4) | H2H | 3 | 100 | 8 | 1 | 74.4% | 80.3% | 57.1% | 3/3 |
| 2021-10-18 | Antwerp | Hard | R32 | 39 |  Marton Fucsovics | 114 | Dennis Novak (Q) | 7-6(4) 6-2 | H2H | 3 | 92 | 5 | 2 | 64.7% | 84.1% | 45.8% | 4/5 |
| 2021-07-26 | Kitzbuhel | Clay | R32 | 74 | Gianluca Mager | 124 | Dennis Novak (WC) | 6-4 6-0 | H2H | 3 | 58 | 3 | 2 | 54.8% | 73.9% | 63.2% | 0/1 |
| 2021-07-19 | Gstaad | Clay | R16 | 14 |  Casper Ruud (3) | 124 | Dennis Novak | 6-4 7-6(5) | H2H | 3 | 96 | 5 | 0 | 62.3% | 92.1% | 65.2% | 0/0 |
| 2021-07-19 | Gstaad | Clay | R32 | 124 | Dennis Novak | 170 |  Kacper Zuk (LL) | 6-4 6-4 | H2H | 3 | 68 | 10 | 1 | 66.0% | 78.8% | 76.5% | 2/3 |
| 2021-07-12 | Bastad | Clay | R32 | 95 |  Pedro Martinez | 122 | Dennis Novak (Q) | 7-5 6-1 | H2H | 3 | 83 | 0 | 2 | 61.0% | 63.9% | 65.2% | 2/4 |
| 2021-06-28 | Wimbledon | Grass | R128 | 74 |  Steve Johnson | 122 | Dennis Novak | 7-6(7) 6-2 7-5 | H2H | 5 | 119 | 10 | 3 | 59.4% | 81.7% | 56.1% | 5/6 |
