| 1998-10-26 | Mexico City | Clay | R32 | 45 |  Dominik Hrbaty (6) | 97 |  Christian Ruud | 6-4 6-3 | H2H | 3 | 59 | 7 | 6 | 54.5% | 73.3% | 48.0% | 7/9 |
| 1998-09-25 | Davis Cup G1 PO: NOR vs CRO | Clay | RR | 299 |  Ivan Ljubicic | 105 | Christian Ruud | 6-1 6-1 6-3 | H2H | 5 | - | - | - | - | - | - | - |
| 1998-09-25 | Davis Cup G1 PO: NOR vs CRO | Clay | RR | 105 | Christian Ruud | 656 | Lovro Zovko | 7-6(5) 6-4 6-1 | H2H | 5 | - | - | - | - | - | - | - |
| 1998-09-14 | Bucharest | Clay | R32 | 84 |  Dinu Pescariu | 99 | Christian Ruud | 6-3 6-4 | H2H | 3 | 69 | 2 | 2 | 69.1% | 81.6% | 58.8% | 2/2 |
| 1998-08-31 | US Open | Hard | R128 | 22 |  Mark Philippoussis | 99 | Christian Ruud | 7-5 6-4 6-3 | H2H | 5 | - | 20 | 5 | 62.3% | 86.4% | 60.0% | 4/5 |
| 1998-07-27 | Kitzbuhel | Clay | R32 | 62 |  Franco Squillari (16) | 105 | Christian Ruud | 6-4 6-3 | H2H | 3 | 66 | 5 | 3 | 62.7% | 65.6% | 68.4% | 1/3 |
| 1998-07-27 | Kitzbuhel | Clay | R64 | 105 | Christian Ruud | 131 |  Alex Lopez Moron | 6-1 6-4 | H2H | 3 | 69 | 0 | 1 | 60.9% | 57.1% | 66.7% | 2/4 |
| 1998-05-04 | Coral Springs | Clay | R32 | 102 |  Ramon Delgado | 151 | Christian Ruud | 6-3 4-6 6-1 | H2H | 3 | 92 | 9 | 2 | 57.7% | 71.1% | 57.6% | 2/4 |
| 1998-04-20 | Orlando | Clay | R32 | 101 | Franco Squillari | 110 | Christian Ruud | 6-3 6-4 | H2H | 3 | 83 | 3 | 4 | 63.4% | 68.9% | 50.0% | 9/11 |
| 1998-04-03 | Davis Cup G1 QF: ROU vs NOR | Hard | RR | 93 | Andrei Pavel | 105 | Christian Ruud | 6-2 6-2 6-2 | H2H | 5 | - | - | - | - | - | - | - |
