Wang Yafan (+95, 168 to 73): The Chinese player's breakthrough came in Miami, where she made it to the fourth round before pushing Angelique Kerber all the way, and she backed it up by reaching the Zhengzhou 125K final and Bucharest QFs (Jimmie48/WTA)
Check out the 15 players in the 2018 year-end Top 100 who improved their position by the greatest amount since their 2017 year-end placement - plus two honorable mentions.