UFC lightweight contender Melvin Guillard was arrested Aug. 13 in Houston for violating probation on a 2007 drug charge, a Harris County deputy told Sherdog.com.

The 25-year-old New Orleans native is in custody at the Harris County jail in Houston, the deputy said last Thursday, and will be released to a drug treatment facility as soon as space becomes available per the terms of his recently amended probation.

Details of the violation were not readily available.

Guillard (21-7-2) was quietly pulled last week from a scheduled bout with Spencer Fisher at UFC 90 on Oct. 25 at the Allstate Arena in Rosemont, Ill. Fisher will now face southern California standout Shannon Gugerty (11-2).

Guillard, who is 4-3 inside the Octagon after a 36-second onslaught on German Denis Siver at UFC 86 in July, was originally arrested on Aug. 3 2007 for possession of a controlled substance (less than a gram). Under a two-year probation finalized on Oct. 10, 2007, Guillard was deferred jail time in favor of a fine, restitution and/or community service, and had to report regularly to a parole officer.

The 25-year-old fighter’s indiscretions have stalled his career before. The Nevada State Athletic Commission suspended Guillard for eight months after he tested positive for Benzoylegonine, a metabolite of cocaine, following his April 2007 loss to Joe Stevenson at UFC Fight Night 9 in Las Vegas.

Guillard admitted to using cocaine six days before the contest, believing the substance would be out of his system within 72 hours.

Calls to Guillard’s management were not returned.

Mike Sloan contributed to this report.