Kentucky's Alex Poythress out for season (knee)

A somber hush hovered over Kentucky basketball players Friday, replacing the jovial atmosphere that usually exudes from this group of Wildcats.

They were just coming to grips with the sudden loss of one of their leaders for the rest of the season, junior forward Alex Poythress.

Willie Cauley-Stein and Dakari Johnson reservedly talked about Poythress' devastating knee injury on a routine layup in practice.

But the top-ranked Wildcats don't have a lot of time to regroup emotionally as they prepare for Saturday's match with No. 21 North Carolina.

''We definitely have to try to get a win for him and just play hard for him,'' Johnson said. ''I know if he was out there, he would play his hardest.''

Poythress, 6-foot-8 and 240-pounds, tore the anterior cruciate ligament in his left knee, the school said Friday. A date for surgery has not been set, but recovery typically takes six to eight months.

Kentucky (10-0) will turn to its depth against the Tar Heels (6-2) to fill the void created by Poythress' injury. He was on the first of the Wildcats' two-platoon system that has been so effective early in the season, winning games by an average margin of nearly 30 points.

Wildcats coach John Calipari seemed to take a wait-and-see view of that strategy as he tried to grasp the sudden loss of a key veteran.

Asked if he would stick with the platoons, the coach said, ''I don't know. I didn't spend any time thinking team last night. ... We will figure (it) out.''

Calipari said on his website Friday that Poythress was injured on a breakaway layup without contact. The injury's freakish nature was what made it so hard for the Wildcats to accept.

''We were just scrimmaging, normal stuff and he was just going up for a fast-break layup and just fell,'' Cauley-Stein said, his voice trailing off. ''We thought he was fine. He could bend his leg and he wasn't feeling the typical ACL injury pain.

''But then they told us after he got the MRI that it was torn. It was crazy.''

Poythress started eight games for the Wildcats (10-0) and averaged 5.5 points and 3.8 rebounds in 20 minutes. The muscular forward was shooting just 38 percent but leads the team at the foul line, making nearly 86 percent. He is third on the team in blocks and sixth in rebounding.

''He can do things that normal (players) can't,'' Johnson said of Poythress.

Pursuing a title was a key motivation for Poythress to return for a third season after last spring's NCAA title-game loss to Connecticut.

Poythress and Cauley-Stein are the most experienced players on a 10-deep roster featuring nine Wildcats at least 6-6. They are featured on the front cover of this year's media guide.

This is the third straight season Kentucky has lost a starter.

Forward Nerlens Noel tore an ACL in February 2013, an injury that ultimately led to Kentucky missing the NCAA tournament. Last spring, Cauley-Stein missed the final three games of the run to the NCAA title game with an ankle injury.

Meanwhile, freshman guards Devin Booker and Tyler Ulis missed Wednesday's 56-46 victory over Columbia with unspecified injuries. Calipari said Friday that both practiced, but didn't say if they would play against the Tar Heels.

Poythress' likely successor on Kentucky's first platoon is 6-11 Trey Lyles, who has grabbed 10 rebounds in back-to-back games while playing mostly on the second squad. Lyles' spot could be filled by sophomore Derek Willis.

North Carolina coach Roy Williams expressed sympathy for Poythress but also said his team is prepared for whatever lineup Kentucky uses.

''You hate it for the kid and he really is a good player and he's done some great things for them,'' Williams said of Poythress. ''You'd have to ask John how it's going to affect them. ... Now they're playing nine guys, unless there's an 11th guy. ... In some ways it might help their rotation (but) I don't think I'll ever say losing somebody helps.''