Former light-welterweight world champion Amir Khan has been handed a two-year ban from all sport after testing positive for a prohibited substance, UK Anti-Doping said on Tuesday.
Khan, 36, returned a positive result for the anabolic agent ostarine following his loss to Kell Brook in Manchester in February 2022.
Ostarine is a drug designed to have similar effects to testosterone.
Khan, who announced his retirement in May last year, accepted a violation of anti-doping rules but said he had not intentionally ingested the substance, an argument accepted by an independent panel following a hearing in January.
The ban is deemed to have commenced on 6 April 2022, when his provisional suspension was imposed, and will expire on 5 April 2024.
Khan became a household name in Britain after claiming a silver medal at the 2004 Athens Olympics, aged just 17.
He made his professional debut in July 2005 and four years later won the WBA light-welterweight title with victory over Andreas Kotelnik in Manchester.
Khan unified the WBA and IBF titles with a win over Zab Judah in 2011 but controversially lost his next fight to Lamont Peterson, who would subsequently test positive for synthetic testosterone.
He retired with a record of 34 wins and six defeats from 40 bouts.
UKAD chief executive Jane Rumble said: "This case serves as a reminder that UKAD will diligently pursue anti-doping rule violations in order to protect clean sport."