Australia: Australian Open - Doubles - Main |
| 1/32-finals | DeVries S./MacPherson D. | Borwick N./Lewis D. | 2:0 (7:5, 6:3) | details | 14.01.1991 |
Switzerland: Geneva - Doubles - Main |
| Final | Albano P./Engel D. | Borwick N./Lewis D. | 2:0 (6:3, 7:6) | details | 16.09.1990 |
| Semi-finals | Cane P./Mezzadri S. | Borwick N./Lewis D. | 1:2 (6:4, 5:7, 6:7) | details | 15.09.1990 |
| Quarter-finals | Borwick N./Lewis D. | Colombo S./Olhovskiy A. | 2:1 (7:6, 3:6, 6:2) | details | 13.09.1990 |
| 1/8-finals | Jonsson L./Strelba M. | Borwick N./Lewis D. | 0:2 (5:7, 0:6) | details | 10.09.1990 |
USA: New Haven 2 - Doubles - Main |
| 1/8-finals | Borwick N./Lewis D. | Fitzgerald J./Jarryd A. | 0:2 (6:7, 3:6) | details | 15.08.1990 |
| 1/16-finals | Caratti C./Herrera L. | Borwick N./Lewis D. | 0:2 (1:6, 6:7) | details | 13.08.1990 |
USA: Long Island - Doubles - Main |
| 1/8-finals | Nelson T./Shelton B. | Borwick N./Lewis D. | 2:1 (6:7, 6:4, 7:6) | details | 13.08.1990 |
United Kingdom: Wimbledon - Doubles - Qualification |
| Quarter-finals | Borwick N./Lewis D. | Foster A./Ireland D. | 0:2 (63:7, 4:6) | details | 25.06.1990 |