Serena Williams, playing in what is likely the final tennis tournament of her storied career, opened singles play with a 6-3, 6-3 victory over Danka Kovinić in the first round of the US Open at Arthur Ashe Stadium.

Williams will face world No. 2 Anett Kontaveit of Estonia in the singles round of 64, also on Wednesday. It will be their first career meeting.

After early struggles with her serve Monday evening, Williams took 10 of the final 13 games against Kovinić, a 27-year-old from Montenegro who is ranked 80th in the world.

After the match, during a ceremony celebrating her tennis career, Williams said she got a boost from the vocal crowd of almost 24,000 people. “The crowd was crazy,” she said.

Williams double-faulted twice in the first game but eventually upped her first serve percentage to 66%. She won 33 of 43 first serve points.

“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,” Williams said in a Vogue article published earlier this month.

“Yeah, I’ve been pretty vague about it, right?” she said with a smile. “I’m going to stay vague because you never know.”

“I think when you’re passionate about something and you love something so much, it’s always hard to walk away,” she said. “Sometimes I think it’s hard to walk away than to not. That’s been the case for me.”

“This match for Ukraine, for my family, for all fans who supported me. I want to say thank you all,” an emotional Snigur said.