WIMBLEDON, England — After watching Serena Williams grimace, hold her side, and double fault six times in a first round victory, Richard Williams said his daughter should not have entered Wimbledon.

“She’s playing hurt, and I don’t think she should be playing,” he said as he walked from Court 2, where Serena defeated Lourdes Dominguez Lino 7–5, 6–0. Williams wouldn’t say much more — “I might lose my job for talking,” he joked — and Serena played down the injury, describing it as a tight hamstring. She said she would remain in the doubles draw, too, where she and her sister Venus, who watched from the stands yesterday, are paired for the first time since 2003.

“It’s gotten better since I’ve been getting treatment on it,” she said. She said she didn’t want to tape it because the tape would chafe her other leg.

“I hate it,” she said.

She declined to explain exactly when the injury occurred, though she suggested she struggled with it at the French Open as well.

“One day I woke up and I was stiff,” she said. “Oh my God, I’m getting old.”

For the record, Williams is 25, though she looked quite a bit older a few times yesterday. She pouted after mistakes and moved slowly. Her serve, usually at least formidable and often invincible, hurt her the most. She served 53% for the match and often pushed her serves long. Dominguez Lino, who lacks power and prefers to play on clay, served for the first set at 5–4 before Williams cleaned up her game.

The question is, how hurt is Williams? If the truth is somewhere between her father’s serious concerns and her modest assessment, it doesn’t bode well for her chances here. The 26-year-old Dominguez Lino, ranked no. 57 in the world, has won one match in a Grand Slam tournament in her career. That she pushed Williams at all is a concern.

Williams faces a much more dangerous opponent next round, Australia’s Alicia Molik. The hard-serving Molik still isn’t the same player who reached the quarterfinals of the Australian Open in 2005, before an inner ear infection sidelined her for the better part of a year. Grass should make Molik’s inconsistency and suspect range less easy to exploit.

Another former Wimbledon champion, Martina Hingis, looked rusty yesterday. Hingis, 26, hadn’t played a match since early May because of a hip injury. Two times in the second set she faced match point against an 18-year-old wildcard, Naomi Cavaday of Britain. Cavaday couldn’t convert, and then she crumbled, 6–7(1), 7–5, 6–0.