Chael Sonnen: Jon Jones tested positive for estrogen blockers

Jon Jones was pulled from UFC 200 after failing a drug test weeks before the event. The interim UFC Light Heavyweight Champion was contrite after his positive test — which was later confirmed with a “B” sample — and said he didn’t even know how to pronounce the substance he tested positive for. But a few MMA insiders have some insight about his failed test.

Last week UFC fighter Rashad Evans said Jones tested positive for estrogen blockers. Chael Sonnen said the same thing Monday on “The Joe Rogan Experience.”

This is unconfirmed information at this point and has not been sourced by actual reporters nor confirmed by USADA — the drug testing agency employed by the UFC.

Estrogen blockers are considered banned substances because they can be used in conjunction with a steroids cycle. Since an athlete taking steroids would have more testosterone in the body, that would lead to a production of more estrogen (a female hormone that can lead to the production of fat and breasts), which is unwanted for male athletes, hence the estrogen blockers.