World champion canoeist Tamara Takács of Hungary is facing a four-year ban after she tested positive for a prohibited substance.
In a statement, the International Canoe Federation (ICF) said the 22-year-old, a three-times European champion, had been informed of the anti-doping rule violation.
It is not yet clear what substance Takács, a member of the women’s K4 crew which claimed the gold medal at the 2017 World Championships, failed for or when the test took place.
The ICF said further details would be announced once the appeal period had expired.
If the ban is confirmed, she would be ruled out of competing at next year's Olympic Games in Tokyo.
Takács won the K1 5,000 metres title at the European Championships and the Under-23 Canoe Sprint World Championships
The Hungarian paddler also claimed the K1 500m and K4 500m titles at the 2017 European Championships.
Takács becomes the latest Hungarian canoeist to have failed a drugs test.
Bence Horváth tested positive in 2017, while double European canoe sprint champion Milan Mozgi was given a four-year ban in November.