Iga Swiatek, a five-time Grand Slam titleholder, has agreed to a one-month ban after testing positive for the prohibited substance trimetazidine, commonly referred to as TMZ, as confirmed by the International Tennis Integrity Agency (ITIA) on Thursday.

The 23-year-old Polish player tested positive during an out-of-competition drug screening conducted in August. The ITIA acknowledged that Swiatek’s positive result was unintentional, attributing it to the contamination of a nonprescription sleeping aid, melatonin, she had been using to alleviate symptoms related to jet lag and difficulty sleeping.

The agency concluded that her degree of fault was assessed to be “at the lowest end of the range for no significant fault or negligence,” indicating that the circumstances surrounding the incident were considered minimally culpable.

Establishing herself as a formidable presence in women’s tennis, Swiatek has held the No. 1 ranking for most of the previous two years, although she is currently sitting at No. 2. Earlier this year, she celebrated a significant achievement by winning the French Open in June, marking her fifth career major title. Additionally, she earned a bronze medal representing Poland at the Paris Olympics earlier in August.