Tan, ranked 113th in the world, was making her Wimbledon main draw debut. Williams has been coming to Wimbledon since 1998, when her opponent was still a babe in arms, reaching 11 finals and winning seven of them.

But you would never have known this from the contest as the 24-year-old Tan rose to the occasion to triumph 7-5 1-6 7-6 (10-7).

"I don't know what to say. I have watched so many times on TV. For my first Wimbledon it is 'wow', just 'wow,'" Tan, on the verge of tears, said.

"When I saw the draw I was really scared - Serena, she's a legend. I was like, 'oh my God! How can I play? I can win maybe one or two games.

"... I play every ball like just, yeah, put some slice, some change, some variety on the game, and it works today.

"It's a dream because, you know, I saw Serena on the TV when I was young. My coach, Nathalie Tauziat, played her 20 years ago."

Tan added Tauziat had told her: "Enjoy because it's your first time in Wimbledon. You play on Centre Court against Serena. Just enjoy the match."

And she certainly did that.

Tan's reward is a second-round clash with 32nd seed Sara Sorribes Tormo. The Spaniard, ranked world No.40, is yet to advance to round three in her two previous attempts.

Her efforts on Tuesday night have, however, caused her to pull out of the women's' doubles in which she was due to partner Tamara Korpatsch.

Tan is understood to have a thigh injury. There is no indication yet as to whether it will affect her continued singles participation.

Australian Associated Press