Serena Williams is unsure whether she will play at Wimbledon again, but says Tuesday's first-round exit has motivated her for future Grand Slams.

Asked whether it would be her last appearance at the All England Club, the 40-year-old American said: "That's a question I can't answer. I don't know.

"Who knows where I'll pop up?"

Seven-time Wimbledon singles champion Williams - who is chasing Margaret Court's record of 24 Grand Slam singles titles - said she did not want Tuesday's loss to be her final memory of a court on which she has had so much success.

"Obviously not," she said. "You know me. Definitely not.

"I gave all I could do. Maybe tomorrow I could have given more. Maybe a week ago I could have given more. But today was what I could do. At some point, you have to be able to be OK with that."

Williams faced Tan almost a year to the day after limping tearfully off Centre Court having hurt her right ankle in her first-round match against Aliaksandra Sasnovich.

She admitted earlier this month - as she made her comeback at Eastbourne in the doubles alongside Ons Jabeur - she had harboured doubts about her future in tennis.

But after losing to Tan, Williams hinted an appearance at her home major - the US Open, which begins in late August - could tempt her to continue training.

"When you're at home, especially in New York and that being the place I first won a Grand Slam, it is always special," she said.

"There's always motivation to get better and play at home."

Ranked 1,204th in the world following her enforced absence, the American great added that, if anything, her performance against Tan had served as fuel to continue.

"It definitely makes me want to hit the practice courts because when you're so close - any other opponent would have suited my game better - I definitely think it's like, OK Serena, you can do it if you want."

She added: "Physically I did pretty good. The last couple of points I was really suffering but I feel like winning those key points is something mentally you have to have.

"If you play week in, week out, or every three or four weeks there is a little more match toughness. You have to think if I was playing matches I wouldn't miss some of those points."