#4 Jelena Ostapenko
The Latvian star had a breakthrough year. Ostapenko actually started the season with two doubles titles before she won her first singles titles. She won the St. Petersburg trophy and the Stuttgart Open.
The breakthrough moment came when she won the French, her maiden Grand Slam title, defeating Simona Halep in the final. She had a 15-3 win-loss record in Grand Slams in 2017 and her second-best performance came at Wimbledon, where she ended up making the quarter-finals.
Ostapenko had a disappointing end to the year as she could not make it past the round-robin stage in the WTA Finals. But finishing the year ranked at a career-best No. 7 was certainly a high point for the 20-year-old.
Edited by Sudeshna Banerjee