Two-time Grand Slam champion Simona Halep announced her retirement from tennis at age 33 after a first-round loss at a tournament in her home country of Romania on Tuesday, ending an injury-filled comeback from a doping suspension.

Halep was a hugely popular first-time Grand Slam champion, well-liked in the dressing room and within the sport in general for her groundedness and apparent lack of ego. Her desperation to win a major was well known and after Halep won in Paris, Martina Navratilova joked: “It wasn’t a monkey off her back; this was an 800lb gorilla.”

To win a grand slam title is something every tennis player dreams of from the day they start swinging their racquet. Despite the difficulty of winning a grand slam tournament, only a select few have dominated on the biggest stage throughout the years.