SAN JOSE, Calif. -- Joe Riggs (Pictures) has been dropped from a co-featured bout against Luke Stewart (Pictures) at Strikeforce "Melendez vs. Thomson" Friday evening at the HP Pavilion in San Jose, Calif.

The California State Athletic Commission denied the Arizona native licensure to fight in the Golden State prior to Thursday's weigh-in for the event.

Both Riggs and Stewart did not weigh in for the bout.

"He did not meet our medical requirements," CSAC Executive Director Armando Garcia told Sherdog.com. "We hope that in a week or so we can receive the right paperwork and we can discuss and clear him to have him fight in California."

Riggs' agent, Ken Pavia, said his client was removed from the card after he disclosed that he'd taken prescription medication a few days earlier. In California, all combatants are required to fill out a pre-fight medical questionnaire listing all medications a fighter has recently used.

"Joe disclosed everything he consumed," said Pavia. "He had a prescription for everything. One of them he took three days ago. [He] wasn't sure if it was going to be in his system."

Pavia said the 25-year-old former state wrestling champion provided documentation of his medication to a CSAC physician, including paperwork for a prescription pain reliever.

After he was told his license would not be approved, an emotional and vocal Riggs was escorted from the weigh-in by his agent Pavia.

Last week, Tim Credeur was also removed from a pending bout against fellow housemate Cale Yarbrough at "The Ultimate Fighter 7" finale in Las Vegas, after he revealed on his pre-fight form that he had taken the presciption drug Adderall a few days before the bout. Nevada State Athletic Commission officials tested Credeur that day through a local lab, and a positive urinalysis result came back the next morning.

CSAC protocol does not allow officials to publicly discuss an applicant's medical information, though Riggs was likely not tested for the drug because he was not officially licensed yet in the state and officials would not have had the jurisdiction to do so.

Riggs had stepped in on a week's notice to face Stewart after Shonie Carter (Pictures) withdrew himself from the bout with a shattered knuckle. The bout was to have been contested at a catch-weight of 178 pounds.

As of Thursday evening, Pavia said he was looking to fill Riggs' slot with another fighter from his roster to face Stewart. CSAC Director Garcia said he would be open to a new opponent provided he was already fully licensed with the state.

Stewart has been touted as one of the more promising up-and-comers in the Strikeforce stable. After cinching five bouts in a row, the San Francisco jiu-jitsu stylist was finally stopped by Tiki Ghosn (Pictures) via decision at Strikeforce's "Shamrock vs. Le" event last March.

In the main event, Strikeforce lightweight champion Gilbert Melendez (Pictures) had no problems making his requisite weight of 155 pounds. Challenger Josh Thomson (Pictures) had more of a struggle. After weighing in at 156 pounds on his first attempt, Thomson disrobed to shed the unwanted extra pound to make Friday's championship bout official.

Strikeforce "Melendez vs. Thomson" Weigh-In Results

Gilbert Melendez (Pictures) (155) vs. Josh Thomson (Pictures) (155)
Bobby Southworth (Pictures) (204.5) vs. Anthony Ruiz (Pictures) (203)
Elaina Maxwell (Pictures) (146) vs. Miesha Tate (145)
Jeremiah Metcalf (Pictures) (185) vs. Raymond Daniels (184)
Chris Cariaso (Pictures) (135.5) vs. Anthony Figueroa (Pictures) (134.5)
Billy Evangelista (Pictures) (155) vs. Nam Phan (Pictures) (154)
Brian Caraway (Pictures) (140) vs. Alvan Cacdus (141.5)*
Cyrillo Padhillo (169) vs. Jesse Jones (169)
Travis Johnson (205) vs. Jorge Interiano (201)
Alexandre Trivino (156) vs. Eric Jacob (Pictures) (156)
Jose Palacios (Pictures) (155) vs. Bobby Stack (155)
Jesse Gillespie (Pictures) (186) vs. Eric Lawson (Pictures) (185)

* Cacdus' second weigh-in still pending