Germany's Angelique Kerber.

Germany's Angelique Kerber capped off her rise to WTA World No.1 by winning her first US Open title, edging past No.10 seed Karolina Pliskova, 6-3, 4-6, 6-4. 
Playing in her first Grand Slam final, the 24-year-old Pliskova did an amazing job in the last two weeks as she beat Venus Williams in the fourth round and Serena Williams in the semifinal, becoming only the fourth woman to beat both Williams siblings in one Grand Slam. 
With the victory, Kerber cements her spot at the top of the rankings, and becomes the first German since Steffi Graf in 1996 to win the US Open title. 
Kerber won her first major titles in Australia and the US, as well as reaching the Wimbledon final, where she lost to Williams, and the Olympic final, where she lost to Monica Puig. 

Source : QNA