KNOXVILLE, Tenn. (AP) — Tennessee will start preseason practice Tuesday without some members of its highly touted freshman class.

Volunteers coach Butch Jones said Monday that wide receiver Preston Williams and offensive lineman Zach Stewart wouldn't be available. Jones said Williams was awaiting word from the NCAA on his eligibility and that Stewart was delaying his enrollment. Stewart's mother died in May.

"We will welcome him when he feels he's ready to come back," Jones said. "And I just ask that you keep him and his family in all of your thoughts and your prayers, as they go through something that's very hard and very challenging in their personal lives."

Tennessee's freshman class already had lost two members in the offseason when receiver Jocquez Bruce and tight end Kyle Oliver left the program.

Williams, a five-star prospect by 247Sports and Scout, was one of the most heralded players in a recruiting class ranked in the top five by multiple services. Jones said Williams' NCAA situation is an "ongoing process," and the coach had no time frame on his potential return.

Williams' absence hampers the depth of a receiving corps that also is missing senior Von Pearson, who was suspended indefinitely in April after being named a suspect in a rape investigation in which no charges have been filed.

"That's one of the areas we're concerned with," Jones said.

Jones said freshman Jauan Jennings, who worked out at quarterback during spring practice, will start out at receiver while continuing to get repetitions at quarterback. Cornerback Malik Foreman also could switch to receiver, though he remains on defense for now.

Tennessee returns the nucleus of a team that went 7-6 last year. The Vols ended a string of four straight losing seasons while playing 23 true freshmen, the most of any Football Bowl Subdivision program.

Jones still sees plenty of room for improvement and cited red-zone efficiency on both sides of the ball as an example.

Tennessee opponents scored on 32 of their 34 trips inside the Vols' 20-yard line last season. Indiana was the only FBS team that allowed opponents to score on a higher percentage of their red-zone possessions.

"That is going to be a point of contention," Jones said. "We have always invested in it, but we will continue to invest in it even more."

Tennessee has plenty of other tasks heading into the Sept. 5 opener with Bowling Green at Nashville's Nissan Stadium. Both starting offensive tackle spots remain open. The Vols also must decide on their main middle linebacker and punter and need to find a top backup to quarterback Joshua Dobbs.

"We can't just be a year older," Jones said. "We have to be a year better. We have to learn from past experiences. We have to be a year wiser."

NOTES: Reserve defensive end LaTroy Lewis will miss the start of camp after undergoing arthroscopic knee surgery. Jones said Lewis should be ready for the season opener. Jones also said defensive lineman Trevarris Saulsberry remains "touch and go" after injuries limited him to a total of nine games over the last two seasons. Other injured players include reserve defensive back Max Arnold and freshman defensive lineman Andrew Butcher, with no timetable set for their returns. ... Jones praised Kansas City Chiefs cornerback and former Vols star Eric Berry for his quick recovery from lymphoma. "We are very excited about him," Jones said. "He is a tremendous story about how you meet adversity head on. Everything is about your temperament and disposition. He is a great illustration for all of us for when we suffer adversity."

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