Moldovan canoe sprint bronze medallist Serghei Tarnovschi has been provisionally suspended from Rio 2016 after failing a pre-Games drugs test.
The 19-year-old claimed third behind gold medallist Sebastian Brendel of Germany and silver medallist Isaquias Queiroz Dos Santos of host nation Brazil in the men's single 1000m final. Russia's Ilia Shtokalov was fourth.
If his provisional ban, which was announced by the International Canoe Federation, is upheld Tarnovschi stands to become the second athlete to be stripped of his medal.
Kyrgyzstan weightlifter Izzat Artykov earlier became the first to lose his medal - also a bronze - after a testing positive for banned substance strychnine.
Tarnovschi had been due to contest the C2M 1000m with brother Oleg, but will now no longer be eligible.