Serena Williams’s next tournament could quite possibly be her last after being defeated by Emma Raducanu at the Western & Southern Open, reports the New York Times.

Williams was defeated in straight sets, 6-4 and 6-0 on Tuesday night in front of nearly 12,000 fans. After the match, Raducanu spoke about being honored to compete against Williams. 

“Well, I think we all need to just honor Serena and her amazing career,” Raducanu said. “I’m so grateful for the experience to be able to play her and for our careers to cross over. Everything she has achieved is so inspirational and it was a true honor to share this court with her.”

“To be honest, I was nervous from the first point to the last point,” Raducanu added. “I know what a champion she is. She can come back from any situation. I just had to stay focused. I’m just so pleased I managed to keep my composure.”

Last week, Williams stunned the sports world by officially announcing that she would retire. In an interview with Vogue, she explained that was leaving the sport that she dominated for almost 25 years.

“I have never liked the word retirement. It doesn’t feel like a modern word to me. I’ve been thinking of this as a transition, but I want to be sensitive about how I use that word, which means something very specific and important to a community of people,” said Williams to Vogue. “Maybe the best word to describe what I’m up to is evolution. I’m here to tell you that I’m evolving away from tennis, toward other things that are important to me. A few years ago I quietly started Serena Ventures, a venture capital firm. Soon after that, I started a family. I want to grow that family.”

Williams is scheduled to play in the U.S. Open in New York which begins on August 29.