Brisbane Broncos player James Segeyaro has been provisionally suspended after returning a positive test for di-hydroxy LGD-4033, also known as Ligandrol, to which Australian swimming star Shayna Jack also tested positive.
The punishment for Jack, who tested positive before the world championships in July, is still yet to be decided and she remains provisionally suspended, like Segeyaro.
The Broncos hooker was tested by the Australian Sports Anti-Doping Authority (ASADA) on September 3, between rounds 24 and 25 of the NRL season.
His A-sample tested positive to the performance-enhancing anabolic agent, which is prohibited by the NRL's anti-doping policy and the World Anti-Doping Agency (WADA) both in and out of competition.
The league and the Broncos were alerted to the positive test on Thursday evening, with Segeyaro "immediately stood down" by the club.
The NRL's statement said it had "spoken with Segeyaro and advised him of support services".
The Broncos had also contacted Segeyaro, who is on holidays, and said they would not comment further while there was an active investigation.
Segeyaro had posted to Instagram within the past day, but his Instagram and Twitter accounts have since been disabled.
The Broncos signed Segeyaro in mid-May in the midst of an injury crisis and later that month he was suspended for a game for drink-driving.
In August, he celebrated his 150th NRL game, with coach Anthony Seibold offering him a new two-year deal.
Segeyaro can now have his B-sample tested under the anti-doping policy, but is prohibited from playing any WADA-compliant sport while his provisional suspension is in place.
