2019 U.S. Open: Highlights From Day 1. United States Open (Tennis), Tennis, Federer, Roger, Djokovic, Novak, Williams, Serena, Sharapova, Maria, Williams, Venus, Barty, Ashleigh, Brooksby, Jenson (2000- ), Gibson, Althea, Murray, Andy (1987- ), Nagal, Sumit (1997- )