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On Monday, the tennis legend paid tribute to the late Off-White designer one year after he died from cancer last November at the age of 41.
Alongside a throwback black-and-white photo of her and Abloh from a Nike campaign photoshoot, Williams, 41, mourned the loss of the fashion powerhouse on Instagram.
"It's been a year and I still can't put into words the sorrow that I feel," she wrote in the caption. "Your touch on the world will live on forever and I couldn't be more grateful to have witnessed it and had the chance to collaborate with you. I still miss you all the time. Forever and ever @virgilabloh ❤️❤️."
While speaking to Vogue in June for a video tribute to Abloh, Williams shared her regret for turning down the opportunity to have worn one of Abloh's most daring designs — the initial envelope-pushing look he designed for her to wear at the 2019 French Open.
"I still kind of regret not doing what Virgil told me to do," Williams said at the time. "He wanted me to wear this long skirt with the crazy train, and then a cape with a train, and then just walk out on the court. And I'm thinking, 'Virgil, I like fashion, and I like pushing the envelope, but this — I just don't think I can do this.' "
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One year after wearing a viral black Nike catsuit (which was later banned from the tournament), Williams opted to sport an Abloh-designed matching crop top, tennis skirt and printed-cape jacket inscribed with the French words for mother, champion, queen and goddess.
But when she saw Abloh soon after the 2019 Open, she made sure to tell the designer that she had made a mistake.
"I just wasn't brave enough to go out there in all the red clay, and just walk out in this train, of like, a Met Gala at the French Open," she recalled.
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Williams' fondness for Abloh –– and his designs –– dates back to 2018 when they first collaborated in an Abloh x Nike collection devoted to the 23-time Grand Slam winner, and at the 2019 Met Gala, Williams wore a pair of Abloh-designed Air Force 1s.
In February, four months after the Off-White designer's death, Williams joined Naomi Campbell, Cindy Crawford, Amber Valletta, and Helena Christensen to walk the runway in the designer's honor at Paris Fashion Week.