LAS VEGAS >> The Nevada State Athletic Commission fined and suspended boxer Julio Cesar Chavez Jr. on today over a failed drug test last year.

The 26-year-old Mexican fighter tested positive for marijuana in September after his first professional loss. Chavez (46-1-1) was suspended for nine months and fined $900,000, which amounts to 30 percent of his $3 million purse for the fight against Sergio Martinez.

Chavez said through a translator that he was sorry for his actions and had taken the drug to curb his stress before the fight.

The commission could have banned him for one year and penalized him for up to 100 percent of his purse.

At a meeting in January, commissioners questioned why Chavez had not yet returned to Nevada for disciplinary action. Attorney Donald Campbell said the former middleweight champion had been stuck in Mexico, unable to obtain a visa.

Chavez’s failed test was revealed Sept. 15 shortly after his dramatic loss to Martinez. Chavez already was fined $20,000 and suspended indefinitely by the WBC, whose belt he lost to Martinez.

In 2009, Chavez tested positive for another banned substance after his fight with Troy Rowland in Las Vegas. He received a seven-month suspension from the Nevada commission.

Chavez was arrested on drunken driving charges last year in Los Angeles, and struggled to make weight for a championship bout last February against Marco Antonio Rubio in San Antonio, Texas.

His promoter, Bob Arum, said in September that he did not see marijuana as a performance-enhancing drug.