Jon Jones was flagged by USADA for a potential doping violation, just three days before his bout with Daniel Cormier at UFC 200, and reports are now saying what substance raised the alarm.
According to Rashad Evans, who was reporting for CBS Sports, someone in Jones' camp confirmed it was two different estrogen blockers which caught USADA's eye.
Jones, who maintains his innocence, refused to name the two substances during his statement following his removal from the card.
Chael Sonnen made a similar comment on Joe Rogan's podcast Monday afternoon.
Sonnen tested positive for two different types of the pro-hormone (anastrozole and clomiphene), which he claimed he used to help him come off testosterone-replacement therapy.
An in depth look at the possible uses for estrogen blockers can be found here.
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