Dokic fully extended by her country collegue Jelena Jankovic in the first set won 7-5, 4-4 when the latter withdrew.
Local favourite Sun also won the first 7-5 but was behind 2-3 in the second when her Italian rival Tathiana Garbin limped off the court conceding the match.
There was another forced retirement when another local player Jie Zheng too conceded the match in the third set against American Jill Craybas who was declared winner.
First round results: Jelena Dokic (Yugoslavia) bt Jelena Jankovic (Yugoslavia) 7-6 4-4 (Jankovic retired); Maria Sanchez Lorenzo (Spain) bt Nicole Pratt (Australia) 6-4 6-3; Tian Tian Sun (China) bt Tathiana Garbin (Italy) 7-5 2-3; (Garbin retired); Jill Craybas (U.S.) bt Jie Zheng (China) 3-6 7-6 (8-6) 2-0; (Zheng retired); Akiko Morigami (Japan) bt Martina Sucha (Slovakia) 6-2 6-3; Anca Barna (Germany) bt Cho Yoon-jeong (South Korea) 6-0 6-2—Agencies