ATHENS, Ga. (AP) - Georgia coach Mark Richt says offensive tackle Kolton Houston is still ineligible because he continues to test positive for a banned performance-enhancing substance he was given for a shoulder surgery more than two years ago.

Houston was Georgia's No. 1 right tackle at the end of spring practice. Richt says Georgia, which opens practice on Thursday, must prepare to be without the third-year sophomore.

Richt says Georgia's medical staff hopes the substance, 19-norandrosterone, will eventually leave Houston's system.

Documents released Thursday by Georgia included an email received Tuesday from NCAA president Mark Emmert, who denied Georgia athletic director Greg McGarity's request for a special exemption for Houston.

Richt said Georgia's staff is ``100-percent certain'' Houston ``has not continued to take this thing.'' Houston can practice with the team.