The 21-year-old Garbine Muguruza has already proved that she has the power and intelligence to reduce the all-conquering American to a nervous wreck when she subjected Williams to a 6-2, 6-2 pummelling at last year's French Open.
A fresh-faced Spaniard who has a love-hate relationship with grass will be eager to prove in Saturday's Wimbledon final that the mighty Serena Williams is as human as the next person with blood, and not ice, pumping through her veins.
'Nerves' and 'Williams' are words that are not usually linked. Such has been the total dominance of the world number one who is gunning for her fourth successive Grand Slam title to complete the "Serena Slam" for the second time in her career.
But 21-year-old Garbine Muguruza has already proved that she has the power and intelligence to reduce the all-conquering American to a nervous wreck when she subjected Williams to a 6-2, 6-2 pummelling at last year's French Open.
"It (the Roland Garros win) is really important because it makes you see and realise that she's also a person. She also has feelings. She also gets nervous," Muguruza said on the eve of her maiden Grand Slam final when she will be bidding to become the first Spanish woman in 21 years to win Wimbledon.
"She knows that I can win against her, that I'm not afraid. I don't think she's really used to this."
While that triumph gave Muguruza the belief that she is capable of competing with the best, Williams also credited that result for her own recent success.
"It was an eye-opening loss for me. Some losses you're angry about, and some losses you learn from. That loss I learned the most from in a long time," said the 33-year-old, who last held all four titles concurrently in 2003.
"I got so much better after that loss. I was able to improve a lot. I worked on things.
"I don't like losing. I really hate losing. So I'm that kind of person that will work harder than anybody else to make sure I don't get that. If I do, I learn from it better."
FAMILIAR LOOK
If Williams thinks aspects of Muguruza's game look familiar, she will only have herself to blame because the Spaniard grew up studying the American's game under a microscope.
"She was an inspiration to me because when I was watching her play finals on TV... it's one of those moments you want to learn how she plays and try to see what you can do to play like her," the Venezuelan-born Muguruza said.
But Williams has only lost three times in 41 matches this year, prompting the Spaniard to say: "She's world No. 1 for something. It's going to be the hardest challenge tomorrow."
Beating Williams at this year's Wimbledon has been beyond the capabilities of former world number ones of the calibre of her sister Venus, twice Australian Open champion Victoria Azarenka and five-times Grand Slam winner Maria Sharapova.
Having toppled the celebrated trio in her last three matches, Williams declared she is at the stage in her career when she has nothing left to prove.
"I've won so many Grand Slam titles. I'm at a position where I don't need to win another Wimbledon. I don't need any titles to make it." said Williams, who is chasing a 21st Grand Slam title 16 years after winning her first.
Muguruza knows that adopting a positive attitude is essential to help her pull off a feat most people think is beyond the Spaniard.
Asked if she can win, Muguruza smiled and said: "Yes, I think I can. I'm playing good. It's true that it's a very difficult match. But I have to believe I can do it."
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