Even as her early losses accumulated, even as Williams got older and was forced to deal with health issues, she never entertained the idea of quitting.
Here she is, at age 34, once again a factor at Wimbledon, site of five of her seven major titles. And there's a matchup against another former champion looming.
Williams overcame a slow start Wednesday for a 7-6 (4), 6-1 victory over 41st-ranked Kurumi Nara of Japan to reach the third round at a Grand Slam tournament for only the second time in her past 10 appearances.
"I don't like watching it on TV. I want to be out there. I'm not about the easy thing. Life is a challenge. For me, when I leave tennis, I want it to be on my own terms. I want to know that I rose to every challenge. I want to look back with no regrets," Williams said. "Everyone messes up. Everyone chokes. Everyone gets tight. Everyone loses matches they should have won. But as long as you walked out there and you gave it your all, you can look back with no regrets."
Williams, a former No. 1 who is seeded 30th, revealed three years ago she was diagnosed with an energy-sapping autoimmune disease.
A year ago, she skipped Wimbledon because of a back injury. She hasn't been to the fourth round at a major since 2011 at the All England Club. But the American will return to that stage if she beats that year's titlist, Petra Kvitova.
"She likes to play on the grass," Kvitova said, "and I'm totally the same."
Williams fell behind 3-0 against Nara, then started finding the mark. In the tiebreaker, Williams again began poorly and trailed 4-1 before grabbing six points in a row for the set.
Nara, 22, spoke about this being a "very special" occasion for her, because she watched Williams on television "when I was a child."
A reporter asked Williams about being the oldest woman left in the tournament, and she jokingly pumped her fists.
"Wisdom has served me well," said Williams, who later returned to Court 3 to win a first-round doubles match with her sister Serena. "I've worn my sunscreen, so I haven't aged terribly. My knees are very tight, not saggy. And the crow's feet have been kept at bay. So I'll give myself an A-plus."
The sixth-seeded Kvitova played with her right leg heavily taped because of a recent injury but had zero trouble in a 6-2, 6-0 victory over 59th-ranked Mona Barthel. The biggest names sent home were No. 8 Victoria Azarenka, the two-time Australian Open champion beaten by Bojana Jovanovski 6-3, 3-6, 7-5; and No. 7 David Ferrer, who lost 6-7 (5), 6-0, 3-6, 6-3, 6-2 against qualifier Andrey Kuznetsov.
Azarenka missed most of this season with an injured left foot and is still working her way back into top form. A telling stat: She converted only 3 of 16 break points, which she called "just ridiculous."
Sam Querrey, an American ranked 67th, was at 9-all in the fifth set against 2008 Australian Open finalist Jo-Wilfried Tsonga when play was halted because of fading light.
In all, the results were nothing like those "Can you believe that?" outcomes of the first Wednesday in 2013, when Roger Federer was among seven players who have been ranked No. 1 to exit the field in less than 10 hours.
The man who defeated Federer that day, Sergiy Stakhovsky, lost his next four Grand Slam matches. But Stakhovsky pulled off another surprise Wednesday, eliminating French Open semifinalist Ernests Gulbis.
Defending champion Andy Murray and last year's runner-up, 2011 titlist Novak Djokovic, both won. Murray's 6-1, 6-1, 6-0 victory over Blaz Rola, who won the 2013 NCAA singles championship for Ohio State, was devoid of drama. That wasn't the case with Djokovic's 6-4, 6-3, 6-7 (5), 7-6 (5) victory over 35-year-old Radek Stepanek, a serve-and-volleyer who tumbled to the grass repeatedly.
On the final point, Djokovic hit a forehand that landed near a line and was called out. Djokovic challenged the ruling, and Stepanek held his hands in a prayer pose, then knelt on the grass, hoping for help. The call went Djokovic's way, though, and the men hugged.
"Around 3 1/2 hours, Centre Court, crowd involved, great points, a lot of entertainment," the top-seeded Djokovic said. "Definitely, I'll remember this match."
In men's doubles first-round action, the third-seeded team of Toronto's Daniel Nestor and Serbia's Nenad Zimonjic defeated Italian duo Paolo Lorenzi and Andreas Seppi 7-6 (5), 6-3, 6-4.
None of the Canadians involved in women's doubles advanced. Eugenie Bouchard of Westmount, Que., and Britain's Heather Watson fell 6-4, 7-6 (3) to Australians Ashleigh Barty and Casey Dellacqua. Toronto's Sharon Fichman and Croatia's Donna Vekic lost 6-1, 6-2 to Japan's Kimiko Date-Krumm and Barbora Zahlavova Strycova of the Czech Republic. And Lucie Hradecka of the Czech Republic and Michaella Krajicek of the Netherlands downed Ottawa's Gabriela Dabrowski and Alicja Rosolska of Poland 5-7, 6-4, 6-2.
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