KNOXVILLE, Tenn. (AP/WVLT) -- Freshman wide receiver Nu'Keese Richardson did not attend Tennessee's brief Sunday night practice.

Volunteers coach Lane Kiffin gave no reason for the absence.

Kiffin said Tuesday he would explain Richardson's absence.

Several Vols (4-4, 2-3 Southeastern Conference) stayed on the sideline during practice for health reasons, but Kiffin didn't rule any of them out for Saturday's game against Memphis.

Starting linebacker Savion Frazier injured his knee late in Tennessee's 31-13 win over South Carolina on Saturday night, but Kiffin said Sunday's diagnosis was better than initially feared.

Defensive linemen Gerald Williams and Marlon Walls were held from practice with ankle injuries, and defensive end Chris Walker missed another day because of a sore lower back. linebacker LaMarcus Thompson sat out after leaving the South Carolina game with a stinger.

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