Former world number one, Maria Sharapova has announced that she is retiring from tennis after an illustrious career that saw her win five Grand Slam titles.

“How do you leave behind the only life you’ve ever known?,” wrote Sharapova. “How do you walk away from the courts you’ve trained on since you were a little girl, the game that you love—one which brought you untold tears and unspeakable joys – a sport where you found a family, along with fans who rallied behind you for more than 28 years?

“I’m new to this, so please forgive me. Tennis—I’m saying goodbye,” Sharapova wrote in an emotional essay.

She became a household name at 17, when she defeated Serena Williams in the Wimbledon final.

Sharapova battled a shoulder injury for most of 2019, a season in which she reached just one quarterfinal. The former No. 1 ended the year ranked No. 145, and lost matches to Jennifer Brady in Brisbane and Donna Vekic at the Australian Open, before calling it a career. She is currently ranked No. 373.

Her career was marked by immense highs and lows. Two years after winning Wimbledon, she claimed her first hard-court major at the US Open, defeating Justine Henin in straight sets, and would win her second two years after that in Melbourne.

“In giving my life to tennis, tennis gave me a life,” Sharapova wrote. “I’ll miss it everyday. I’ll miss the training and my daily routine: Waking up at dawn, lacing my left shoe before my right, and closing the court’s gate before I hit my first ball of the day. I’ll miss my team, my coaches.

“I’ll miss the moments sitting with my father on the practice court bench. The handshakes—win or lose—and the athletes, whether they knew it or not, who pushed me to be my best.”

Sharapova admitted that she had tested positive for the recently banned substance Meldonium at the 2016 Australian Open, where she had reached the quarterfinals. A 24-month suspension—later reduced to 15 months—marked the beginning of the end for Sharapova’s status as a bonafide threat on tour.

Sharapova, who turned pro in 2001, first reached No. 1 in August of 2005, and won a total of 36 singles career titles, 645 singles matches and more than $38 million in on-court prize money.

“There are a few simple things I’m really looking forward to,” she wrote. “A sense of stillness with my family. Lingering over a morning cup of coffee. Unexpected weekend getaways. Workouts of my choice (hello, dance class!)”

The Russian retires as one of only 10 women to have won each of the sport’s four Grand Slam titles, and as a former world number one.