Junior flyweight title holder Omar Nino of Mexico tested positive for methamphetamine -- better known as the highly addictive drug crystal meth -- in his post-fight urinalysis following a Nov. 18 title-retaining draw against Brian Viloria at the Thomas & Mack Center in Las Vegas, according to the Nevada Athletic Commission.
Keith Kizer, commission executive director, also told ESPN.com on Wednesday that another fighter on the card, junior featherweight Joksan Hernandez, 20, of Mexico, also failed a post-fight drug screen. Hernandez (11-1, 6 KOs), who lost a 10-round decision to Bernabe Concepcion, tested positive for marijuana, Kizer said.
Both fights were on the card headlined by the rubber match between Manny Pacquiao and Erik Morales.
Nino's title is in jeopardy as the WBC probably will strip him, although no ruling has been made yet.
Nino (24-2-2, 10 KOs) was making the first defense of the title he won from Viloria on an upset decision in Las Vegas in August.
"We're shocked that something like that occurred," said Todd duBoef of Top Rank, Nino's co-promoter. "I talked to (co-promoter Fernando) Beltran, who said the kid insists he never took anything."
Kizer said a third fighter, cruiserweight Dewey Cooper (15-0-2, 10 KOs) of Las Vegas, tested positive for the banned diuretic Lasix, after a fourth-round knockout of Salah Zabian on Top Rank's Nov. 16 card at the Hard Rock resort in Las Vegas.
Kizer said he has issued complaints against all three fighters, who will be temporarily suspended at a Dec. 5 commission meeting pending a full disciplinary hearing, which will probably take place in January. Kizer said he had notified handlers of each fighter about the test results.
The fighters face possible fines and suspensions, Kizer said. In addition, if the commission rules that the fighters took the drugs, the results of the bouts would be changed to no decisions.
Nino, 30, is the second title holder this month to flunk a post-fight drug screen. Orlando Salido, who won a featherweight world title from Robert Guerrero on Nov. 4 in Las Vegas, tested positive for the banned steroid Nandrolone in his post-fight drug screen and was stripped of his IBF belt. His case is also on the Dec. 5 commission agenda.
"Four guys, four different drugs. It's amazing," Kizer said. "I wish it was none."
Dan Rafael is the boxing writer for ESPN.com.