By Keith Idec

Billy Joe Saunders reportedly has failed a performance-enhancing drug test that has jeopardized his upcoming middleweight title defense against Demetrius Andrade.

According to an ESPN.com report Thursday, Saunders has tested positive for oxilofrine, an amphetamine that can enhance endurance. The positive test could cause the cancelation of the WBO middleweight champion’s fight versus Andrade on October 20 at TD Garden in Boston.

England’s Saunders (26-0, 12 KOs) likely will be stripped of his WBO 160-pound championship as well, ESPN.com reported.

Andrade (25-0, 16 KOs), of Providence, Rhode Island, is the mandatory challenger for Saunders’ title. If Saunders is stripped, the No. 1-ranked Andrade could fight someone else for the vacant championship October 20.

Namibia’s Walter Kautondokwo (17-0, 16 KOs) is the WBO’s No. 2 contender for its middleweight title.

Failing a test administered by the Voluntary Anti-Doping Association marked the continuation of a troublesome year for the polarizing Saunders.

The skillful southpaw was supposed to make an optional title defense against England’s Martin Murray on April 14 at O2 Arena in London. The 29-year-old former Olympian withdrew from that fight due to a hand injury and from their rescheduled June 23 bout with a hamstring injury.

Murray accused Saunders of faking his second injury because Saunders was trying to land a more profitable fight against Gennady Golovkin. Saunders agreed to battle Golovkin on August 25 at The Forum in Inglewood, California, but that plan was scrapped once Golovkin (38-1-1, 34 KOs) and Alvarez (50-1-2, 34 KOs) agreed to terms June 13 for their rematch September 15 at T-Mobile Arena in Las Vegas.

Instead of challenging Golovkin for middleweight supremacy, Eddie Hearn, Andrade’s new promoter, and British rival Frank Warren, who works with Saunders, came to an agreement for their WBO-mandated championship match July 25, just before a purse bid scheduled for later that day.

The WBO ordered a Saunders-Andrade title fight because Brooklyn’s Daniel Jacobs (34-2, 29 KOs), then the WBO’s No. 1 middleweight challenger, reached an agreement to fight Ukraine’s Sergiy Derevyanchenko (12-0, 10 KOs) for the vacant IBF middleweight title October 27 in The Theater at Madison Square Garden.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.