Serena Williams is halfway to starting her U.S. Open with a victory after taking the first set 6-3 against Danka Kovinic. Williams won the first two games, dropped the next three, and then regained her grip before closing it out in 55 minutes. Williams has said she is preparing to end her tennis career, but a victory would send her into a second-round match against No. 2 seed Anett Kontaveit of Estonia.