KNOXVILLE -- When Derek Dooley opened up his first preseason camp as the University of Tennessee's football coach a year ago, much of what his first team would look like was a mystery.

Players stepping into newer and bigger roles all over the field, new systems on offense and defense and a new coaching staff with different goals and a different style.

With a class of inherited players gone and replaced by a group of players he's recruited, Dooley might have a better grasp on his team entering his second year.

But there's those 26 new players and roughly 30 other second-year players about whom to worry.

"Our storyline is we're young but I feel good about the talent we have," Dooley said at Southeastern Conference media days last week. "We entered this spring saying we're not going to let our youth be an excuse for failure. We're not, and so it's going to be everybody's responsibility not to act like freshmen and sophomores and not to play like them. We'll see if they can do that."

The Volunteers report to camp today with 26 new faces and even more guys back for year two. Freshmen and sophomores comprise more than 70 percent of UT's roster.

A handful of players that signed with UT in February and arrived on campus in June will be counted on to make immediate impacts, and the group of sophomores that made exciting impacts last season must take the next step.

Whether or not both groups of players can do that is the great unknown.

"I don't know how all these young guys are going to be able to do it week in and week out, and that's going to be the telltale sign of what our season is this year," Dooley said.

"I left spring feeling pretty good about what we accomplished as a team knowing that we have a long way to go and knowing that we were going to need help by the 20-something guys that were going to come in this fall. There's a lot of unknown. I hadn't seen any of these young freshmen coming in, still really haven't other that looking at them, so there's a lot of unknown."

The new Vols might be less of an unknown to their older teammates, who have spent a whole summer with them in the setting of the summer workout program. Though it wasn't a consensus top-five recruiting class nationally, UT's 2011 class created excitement about what its future might hold.

"They're all looking good, [but] I haven't really gotten to look at them too much," senior defensive lineman Malik Jackson said. "I still just call them freshmen. I don't even know half their names, but they're coming along pretty well.

"I expect greatness from all of them, but we've just got to keep working them to their potentials so on Saturdays they can show everybody else their greatness."

The coaching staff has tried to prepare the new players as best they can, whether by sending them parts or all of the playbook in advance or by conducting seminars with the goal of teaching integrating them into the high standards expected from them on and off the field.

"This freshman class definitely doesn't act like a freshman class," senior tailback Tauren Poole said. "They're a phenomenal class because they're very mature. They're ready to work and they love to compete. I like to see it, and I know they're going to be great in a few years and maybe even a few this year. I'm excited about it."

The excitement, though, comes with plenty of nervousness and uncertainty as well. How the new players adjust to their first taste of college football is never consistent. The Vols' coaches have higher expectations for some guys -- such as defensive tackle Maurice Couch and defensive back Byron Moore, both junior college transfers -- and could expect less from others.

How each and every player will handle or meet their individual levels of expectation is, at best, hit or miss. The questions begin to be answered when the Vols open practice Tuesday, and Dooley will likely split up the veterans and the younger players for the first few practices like he did last year. The pads go on Sunday.

"We really won't know anything until we get in pads," Jackson said. "You can't do anything in seven-on-seven [drills] like tackling or hitting. We'll see when we put on the pads, but all the freshmen are looking good and looking like they can help.

"There's going to be a lot of competition this year."