Ryan Garcia has been handed a one-year ban from boxing by the New York State Athletic Commission after failing a drugs test.
The 25-year-old tested positive for banned substance ostarine in two separate tests taken before his fight with Devin Haney on 20 April.
Garcia’s victory against Haney will now be recorded as a no-contest – meaning Haney’s undefeated record is restored.
As well as the ban, Garcia must forfeit his £950,000 ($1.2m) contract purse from the Haney fight and pay a £7,900 ($10,000) fine.
Garcia, who denied taking the substance, blamed “contamination” from a tainted supplement.
Garcia, who wrote on X on 19 June that he was “retired”, responded to the ban by saying: “I was already retired so I’ll just come back out of retirement for a year.”
The American added: “I never cheated.”
Garcia has just one defeat on his 25-fight record, a 2023 loss to Gervonta Davis, and is considered one of the biggest stars in American boxing.
His voided victory against Haney came in New York, with Garcia winning on points after missing weight before the contest.
Haney, whose record returns to 31 victories in 31 fights, said on X: “Thank you to commission for doing the right thing and making the right decision.
“I’m happy it wasn’t a DQ [disqualification] because I wouldn’t want [to] win like that.
“Once this suspension is over, Garcia let’s run it back. Clean on a even playing field. Biggest fight [in] boxing.”
Ostarine, a non-steroidal drug used to support muscle growth, has been on the World Anti-Doping Agency’s banned substance list since 2008.
BBC Sport has contacted the New York State Athletic Commission and Ryan Garcia’s team for comment.