Serena Williams, arguably the greatest athlete of all time, is competing in her 11th US Open in her career. This year also marks her return to the competition, after missing the 2017 open because she was pregnant with her daughter Olympia. To mark the occasion, Nike released a touching ad that includes footage of Serena training as a young girl with her father.

In the ad, Williams’ father and coach Richard tells a young 9-year-old Serena to serve as if she’s playing in the US Open. The home video, taken in 1991, then cuts between Serena’s six US Open–winning championship matches.

If Serena wins another singles championship, that will tie her with Margaret Court for the most Grand Slam single titles ever, with 24.

Williams recently faced controversy at the French Open, after the French Tennis Federation banned the Nike catsuit she wore during the competition. But the legend wasn’t too bothered. “When it comes to fashion, you don't want to be a repeat offender,” she said. “I think that obviously the Grand Slams have a right to do what they want to do.”  

Nike weighed in, too.

The US Open began Aug. 21 and will go on until Sept. 9. You can check out a schedule of Williams’ matches here.