With five McDonald's All-Americans, Kentucky will have as much talent top to bottom as any team in college basketball this season.

The Wildcats, who are expected to begin the year ranked inside the top-5, also sport a lot of length, with eight players 6-foot-6 or taller and seven with 7-foot-plus wingspans.

UK returns 27 percent of its scoring from a season ago, a relatively high number in the John Calipari Era. Defensively, Calipari thinks this squad has the potential to be one of his best defensive teams.

"Our defense on the ball should be unbelievable," Calipari said at media day last week. "I think we're long enough that other positions, if you try to beat us to the rim, we can block shots. That's the sign of a really good defensive team."

So what is it that keeps the Kentucky head coach up at night?

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"Are we going to be physical enough?" Calipari said. "If you get roughed up, can you still play, can you still perform? Do we have the physical, mental toughness? In the games we got to get them to understand that we're going to have to take this up a notch. So the main thing for me will be how do we rebound and how tough are we physically?"

One player Calipari mentioned specifically is freshman forward Keion Brooks, who is listed at 6-foot-7 but a slight 205 pounds.

"He's a good basketball player. He's got a good feel for the game. Physically he has to catch up," Calipari said. "He knows. He's long, he's active, he plays rough, physically, his body's got to catch up to everything else. He may play some stretch 4 for us because he gives us that length and size and ability to space the court. And it's hard for 4s to guard him, even EJ struggles to guard him at times. He can do things with that ball, and a lot of stuff he starts like he's a guard. But he's big."

After failing to sign an additional big man this summer, the potential of a small ball lineup has been one of the offseason's major storylines. If the Wildcats try to go small, that means other teams are going to try to go big and Kentucky's biggest big is Nate Sestina, who at 6-foot-9, is down to 235 pounds after playing at closer to 250 for Bucknell last season. And Calipari says Sestina is closer to a four than a five.

"To be honest he's like a stretch 4," Calipari said. "He shoots it, good with the ball. He can play some 5, but if you play him at 5 you're going to stretch the court with him as a 5 and probably post somebody else. But he's good in the post. He's really been a great addition to this group."

After being pushed around by PJ Washington and Reid Travis last season, Calipari is hopeful 7-foot junior center Nick Richards has finally turned the corner physically.

"Right now he's really playing well and he's playing confident and the expectation is this is his time," Calipari said. "But again, you got to get on the court, and now you're playing against a football player that's trying to just say, 'I know I can't play you, I'm going to try to rough you up.' Can you hold your ground? Can you sustain your confidence in that kind of situation? Until we start playing games, who will know? Now, my hope is he's ready for it."

Richards wasn't alone in getting roughed up by UK's starting frontcourt from a season ago and EJ Montgomery is hoping to ride an improved physicality to a Washington-esque leap as a sophomore this season.

"I've been in the weight room a lot and that's been my main focus, just getting more physical," Montgomery said. "This year, I'm definitely going to be ready. I've definitely made some improvements with my strength. Been working on physicality every day with rebounding drills, charge drills, diving on the floor and things like that."

Kentucky won't have to wait long for its first physical test. The Wildcats will face off with likely preseason No. 1 Michigan State at the Champions Classic in the season opener on Nov. 5. Tom Izzo's Spartans are generally regarded as one of the most physical teams in the country.