That she rattled past Uzbek Iroda Tulyaganova 6-3, 6-2 in a Group A match was almost incidental as all thoughts were immediately on Friday's much-anticipated clash with the world number one.
Clijsters -- surprise winner over Williams in the final of 2002's year-ending WTA Championships -- says she hopes she has discovered the "magic formula" to beating Serena and elder sister Venus.
Williams, on the other hand, smiles sweetly before putting that November defeat down to fatigue.
Behind the smiles, Serena is clearly stung by the loss in Los Angeles and is determined to set the record straight.
"Oh, it should be fun," she smiled when asked about the match-up. "I'm just going to have fun, basically."
In the Williams' handbook, fun does not include losing and she is it at pains to make it clear that November's slip-up was a mere blip.
"Honestly, I'm just feeling better than I was then. I'm just happy that this is not LA," the 21 year old said.
"Oh my gosh, it was too much tennis at the end of the year -- mentally I was shot and physically I was dead. But it's good to see her doing so well she is such a nice girl."
Clijsters certainly won't be going into Friday's match with a "nice girl" mentality.
"I'm feeling very fit at the moment," she warned, "I'm looking forward to it very much."
When asked if she has found the formula to beating the powerful Williams sisters, the 19 year old beamed: "I hope so.
"It is just a matter of being a little more consistent than I was at the beginning of last year. I think I am capable of doing it."
At the Hopman Cup, Clijsters has been in devastating form. She has lost just six games in two matches, having obliterated Spain's Virginia Ruano Pascual 6-1, 6-0 in her opening tie.
Williams, by contrast, has looked a little rusty in the early matches.
She will have to dig deep and find her top tennis in the next 24 hours if she is not to fail in her quest just three days into 2003.
