WIMBLEDON, England (AP) - When Serena Williams talked up her chances of winning a third Wimbledon title, she never mentioned anything about an injury.

She didn't count on her father revealing that she's not 100 percent fit.

"I'm going to have to talk to my dad," Williams said. "I'll probably let him slide this time."

Williams reluctantly acknowledged that she has been receiving treatment for what she called a "tight" hamstring, which may explain her erratic start to her first round match Monday at the All England Club.

Williams was down 5-4 in the first set, spraying unforced errors and looking out of sorts. She managed to lift her game and win nine straight games to beat Lourdes Dominguez Lino of Spain 7-5, 6-0.

"It's good she got through the match, but she looks like she's playing a little hurt. I don't think she should be playing. I told her she shouldn't," her father and coach, Richard, said after watching the match.

Then, with a laugh, he added: "You'll have to ask her about what the injury is or I might lose my job for talking."

On Saturday, Williams said she and her sister, three-time champion Venus, were "healthy" and ready to go. When told of her father's remarks, she wasn't enthused about discussing the ailment and gave few details.

"It's doing OK," she said. "I'm just taking it a day at time. It's getting better, better than it was a couple days ago. Flared up, but it's getting better now, slowly but surely."

Pressed on how it could affect her tournament, the eight-time major winner said, "I'm hoping and praying it will get better in time. It's gotten better since I've been getting treatment on it."

Williams didn't think the leg problem affected her serve, even though she finished with six double-faults.

"Honestly, I did feel a little limited," she said. "But I think if things had been tougher, I would have fought through it."

"I raised my game on some points, which I think was the big difference," Williams said. "Out of a 10, I was probably at a 2, maybe."

The state of her fitness will surely be of interest to her main title rivals.

That includes top-seeded Justine Henin, who beat Argentine qualifier Jorgelina Cravero 6-3, 6-0 to renew her bid for a first Wimbledon title to complete a career Grand Slam.