Shelby Walker (Pictures), one of the better known American female mixed martial artists, was found dead Saturday evening from what her manager Larry Goldberg called an overdose of pain medication.

Walker, who competed under the American Top Team banner, was 31 years old.

"She was a wonderful person who inspired many people," Goldberg said in a statement released on Walker's Web site. "However she succumbed to personal demons. Shelby was loved and will be greatly missed by all that knew her."

Walker fought to a 2-3 record in mixed martial arts, but her real passion was boxing. In April, Walker fought what it turns out would be her final boxing bout, losing by TKO to Mia St. John. In all, Walker, a native Texan, compiled a 7-6-1 (6 KO) record in the ring.

Her crowning moment in MMA came in May 2003, when "Shelby Girl" knocked out Angela Wilson in just five seconds.

Said Goldberg: "Shelby should be remembered as the fun loved beautiful person who was the life of any party and got to live her dream."