A probable suspension awaits Michel Rivera following the first loss of his pro career.

The Dominican lightweight remains under indefinite suspension by the Nevada State Athletic Commission, which BoxingScene.com confirmed stems from a positive drug test surrounding his lopsided defeat to Frank Martin last December 17 at The Cosmopolitan in Las Vegas. Rivera tested positive for hydrochlorothiazide and triamterene, both of which are on the banned list under World Anti-Doping Agency (WADA) code.

The matter remains under investigation by Nevada commission officials, who agreed to extend the temporary suspension pending further review.

Hydrochlorothiazide and triamterene are both considered diuretics and largely identified as water pills. The combination of the two help reduce fluid retention and reduce blood pressure.

Rivera and his team contend that he ingested the substances unwillingly after being duped into believing he was taking vitamins and supplements. The claim has been met with sympathy but is unlikely to help reduce any forthcoming punishment, as all athletes are responsible for what enters their body.

Similar instances normally result in a nine-month suspension issued by the Nevada commission, along with a fifteen-percent fine of the contracted fight purse. Such punishment will leave Rivera out of the ring until September, as the suspension is retroactive to the time of the infraction which occurred last December.

The development further crushes any momentum gained by Rivera (24-1, 14KOs), who—along with Martin—enjoyed a three-fight 2022 campaign.

Both boxers were undefeated entering their WBA-sanctioned lightweight title eliminator, which saw Martin (17-0, 12KOs)—who is promoted by unified welterweight titlist Errol Spence’s Man Down Promotions—floor Rivera in round seven en route to a lopsided win by scores of 117-110, 118-109 and 120-107.

Rivera was rumored to have struggled to shrink his filled out 5’9” frame to lightweight, though he weighed 134.4 pounds on the official Nevada State Athletic Commission scale during the pre-fight weigh-in. He was roughly the same weight in an eight-round points win over Jerry Perez just two months prior in Brooklyn, New York, as well as in his eighth-round knockout of Spain’s Jon Fernandez in their July 2021 WBA semifinal eliminator in Carson, California.

The instance in question is the first time that Rivera has run into such an issue and is generally regarded as a clean fighter. The 24-year-old from Miami by way of Santo Domingo, Dominican Republic is long enrolled in the WBC Clean Boxing Program.

However long the suspension, Rivera is expected to campaign in the 140-pound junior welterweight division upon his ring return later the year.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox