Simona Halep has recently been best known as the player who ended Marion Bartoli’s career, bringing the Wimbledon champion to tears after defeating her in Cincinnati.

Yet few recognize that Halep entered the United States Open on the hottest run of any player. Halep, a 21-year-old Romanian who is seeded 21st, has won 31 of her last 36 matches, with her most recent victory, a 6-2, 6-1 win against Donna Vekic, coming in the second round of the Open on Thursday.

She won her first title in June, but since then, she has earned four of them. When she won at New Haven before the Open, she secured the No. 19 ranking.

Her emergence has been sneaky and sudden, just like the other Romanian women on the tour. Five rank in the top 75: Sorana Cirstea (22), Monica Niculescu (42), Alexandra Cadantu (73) and Irina-Camelia Begu (74).