Caroline Wozniacki is the world number one, but she goes into a heavyweight women's semi-final at the US Open on Saturday very much the challenger to three-time champion Serena Williams.
The final four match on Saturday night will have a championship flavour, but a defiant Wozniacki insists she doesn't need to pass any test posed by Williams to prove herself worthy of her top ranking.
"I don't care what people think and say or do," Wozniacki said. "I go out there, and what I care about is that I give 100 percent every time. You win a match, you lose a match sometimes. It's sports.
"I know I'm going out there and playing a great champion. She hasn't won 13 Grand Slams for nothing. She's been out there on the big stage many times.
"I'm No. 1 in the world at the moment and I've been playing well and I have had a great year...
"We'll just go out there, and hopefully it will be a good battle," she said. "That's all that matters, that I give it my all. After the match we'll see how good that was."
The winner will face either ninth-seeded Australian Samantha Stosur or unseeded German Angelique Kerber in a women's final that has been pushed back to Sunday after heavy rain washed out two days of play.
Stosur, the 2010 French Open runner-up, toppled world number two Vera Zvonareva in straight sets to keep alive her hopes of reaching a second career Grand Slam final.
Kerber, ranked 92 in the world, is in uncharted territory having never made it past the third round of a major until this week.
But there's no doubt Wozniacki-Williams will be the main event on Saturday night.
The clash of the titans of the women's field falls before the final thanks to Williams' lowly 28th seeding.
After health woes ranging from foot surgery to dangerous blood clots sidelined her for 11 months, the younger Williams sister has roared into contention for a 14th Grand Slam singles title, more than a year after claiming her last at Wimbledon in 2010.
Williams, who won hardcourt titles at Stanford and Toronto in the run-up to the Open, said once she gained confidence in her well-being, confidence in her game was quick to follow.
"I came to New York to see my doctor, and he gave me a clean bill of health," she said. "Ever since then I played without thinking that something could happen, so that's a really good feeling."
Williams and Wozniacki have met twice before, both times in 2009. Williams won the first match and Wozniacki retired from the second.
While her runner-up finish to Kim Clijsters in the 2009 US Open remains Wozniacki's best Grand Slam performance, her six titles this year are a testament to the consistency that is often cited as her greatest attribute.
"I think her weapon is the fact that she never gives up," Williams said. "That's probably the biggest weapon I think you can have in all of tennis."