LAS VEGAS (AP) - A Nevada regulator says boxer Lamont Peterson
failed a drug test, and a May 19 rematch in Las Vegas against former title holder Amir Khan is in doubt.

Nevada Athletic Commission executive Keith Kizer tells The Associated Press that he learned Monday that the WBA (super) and
IBF light welterweight champion tested unacceptably high for synthetic testosterone in a urine test administered in March by the Las Vegas-based Voluntary Anti-Doping Association.

Kizer says separate tests on a second sample from the 28-year-old Peterson were found positive on May 2.

Kizer says Peterson's lawyer is promising an explanation.

But as of Tuesday, Peterson has no license to fight Khan as scheduled next week at the Mandalay Bay resort.

Kizer says Peterson won't get a license unless the matter can be
resolved.

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