Angelique Kerber (German: [andʒɛˈliːk kɛɐ̯ˈbɐ]; born 18 January 1988) is a German professional tennis player who is currently ranked world No.1 in women's singles tennis by the Women's Tennis Association (WTA). Having made her professional debut in 2003, Kerber rose to prominence upon reaching the semifinals of the 2011 US Open, at which time she was ranked no. 92 in the world. She achieved a career-high ranking of world No. 1 on September 12, 2016, becoming the twenty-second and oldest player to achieve the number one ranking for the first time. At the 2016 Summer Olympics, Kerber won an Olympic silver medal while representing Germany. A left-hander known for her aggressive counter-punching all-court game, Kerber has won 10 singles titles, most notably her two major titles—the first at the 2016 Australian Open, and the second eight months later at the 2016 US Open. She has won at least one title on every surface on the WTA Tour, achieving this feat in 2015 by winning Charleston (green clay), Stuttgart (red clay), Birmingham (grass) and Stanford (hard).