Serena Williams Signed Vest comes professionally framed with a certificate of authenticity on the back. Serena Jameka Williams is an American professional tennis player. She has won 23 Grand Slam singles titles, the most by any player in the Open Era, and the second-most of all time behind Margaret Court (24). The Women’s Tennis Association (WTA) ranked her singles world No. 1 on eight separate occasions between 2002 and 2017.