ARLINGTON, Texas -- When Sean Lees left leg slid out from under him and he didnt get up, teammate Barry Church figured the Dallas Cowboys were in for some bad news on the first day of off-season practice. The fifth-year safety also knew Dallas defensive leadership was shifting his direction. "I was right behind him when it happened," Church said Wednesday, a day after Lee tore the anterior cruciate ligament in his left knee and put his season in jeopardy. "And thats one of my best friends on the team. Feels kind of awful. But we have his back no matter what." Cowboys coach Jason Garrett refused to offer any details on Lees injury after participating in a home run derby for charity at the home of the Texas Rangers. The team reported on its website that Lee has been told he has a torn ACL. Even with a quick recovery from such an injury, Lee wouldnt be ready until the second half of the season. His teammates talked like they were expecting to be without the linebacker who hasnt played a full season in his four years in the league. "You always have to stay positive," cornerback Brandon Carr said of a defence that was plagued by injuries a year ago and finished last in the league and is now without Lee and career franchise sacks leader DeMarcus Ware, who was released in March. "Its a very unfortunate situation -- a guy that works his butt off each and every day. He brings a lot to the table, but at the same time its the next man up mentality." First on that list might be Church, who assumed a leadership role when Lee missed the final three games last year with a neck injury and is versatile enough to fill the role of a linebacker for a few snaps. Church missed the last 13 games in 2012 with a torn Achilles tendon before bouncing back last year with the first 16-game season of his career. If the Cowboys are to break a three-year rut of 8-8 finishes and a four-year playoff drought, plenty will fall to him. And Lee has already told him that. "Me and a couple of the other guys are going to have to take over that defence, just lead the younger guys in the right direction," Church said. "Feel like we can do that." The oft-injured Lee went down during the 11-on-11 portion of Tuesdays practice. His left leg slid out from under him as rookie guard Zack Martin was closing in for a block, and Martin rolled over him. Contact isnt allowed in off-season workouts, but blockers frequently engage linemen and linebackers before plays stop in 11-on-11 drills. Lee was already on his way to the ground when Martin lunged over him. "I dont really know what happened," said Martin, the Cowboys first-round pick at No. 16. "Two guys playing hard, running to the ball." The 27-year-old Lee hasnt played a full season in four years. The middle linebacker has missed 15 games over the past two years, including five of the final six games in 2013. Lee signed a six-year extension worth up to $51 million last year, but durability-based incentives are built into the deal. Hes already likely to miss out on a bonus in 2015 for not playing enough snaps in 2013 or the coming season. When healthy, Lee is among the most productive linebackers in the league, leading his position with 11 interceptions since entering the league in 2010 despite missing 18 games. But his injury history dates to his college days, when he also tore a knee ligament during off-season workouts. The right ACL injury in spring practice in 2008 kept him out that season, pushing his senior year to 2009. He was already back at the teams practice facility a day after his latest injury, going over plays with some of the younger players. That group includes rookie fourth-round pick Anthony Hitchens, who could get a shot at replacing Lee. "He wants to win, if hes on the field or not," Hitchens said. "It means a lot to me, being a young guy that hes helping me out already. Hes been here for a while, so he knows all the pieces of the puzzle. So I always go to him and ask questions." Not that he wants it, but Lee apparently will have plenty of time to answer them. Billigste Nike Air Max . Monta Ellis had 30 points and nine assists, Nowitzki was another of seven Dallas players in double figures with 11 points and the Mavericks beat the Los Angeles Lakers 123-104 Tuesday night. Nike Air Max Tilbud . - Novak Djokovic beat John Isner 7-5, 6-7 (2), 6-1 on Saturday to reach the final of the BNP Paribas Open, where hell resume his longtime rivalry with Roger Federer. http://www.airmaxdanmark.com/ . Amaro broke the NCAA all-time record for receiving yards in a season for a tight end with 1,352 during his junior campaign, eclipsing the mark of 1,329 set by Rices James Casey in 2008. Air Max Dk . - Tom Brady and the Patriots routed the Bengals and quieted the doubters. Billige Nike Air Max . He will play 10th-seeded Feliciano Lopez in Sundays final, after the Spanish left-hander defeated Radek Stepanek of the Czech Republic 7-6 (7), 6-4.Southampton manager Claude Puel says Saturdays opponents Liverpool have to be considered among the title favourites. But Puel says his team are more than capable of competing with the Premier Leagues big guns and is expecting them to give a good account of themselves.Saints are 10th in the table, having made a solid start to life under Puel, but Liverpool are sitting atop the standings, with eight wins and just one defeat from their first 11 games. Six months half price Upgrade to Sky Sports to watch Man Utd v Arsenal on Saturday and get the first six months half price They are one of the favourites, of course, said Puel at his Thursday press briefing.Like Arsenal, Manchester City, and other teams, they are at a very good level for this league this season, but my players can play a good game against these teams too.Its important for my team to play our football, our game.We play against a very good team, with good players and spectacular football, but I think we have qualities also.They are first in the table for chances against opponents, and we are in third position with this statistic.We can see a good, open game and I hope we will have a good result at the end for the supporters but its important to stay with our good football and concentrate on this. Charlie Austins goals have rescued Southampton at times this season He hopes the rest of his squad can start to take some pressure off Charlie Austin, who has scored five of thheir 12 Premier League goals this season.dddddddddddd.Hes efficient in front of goal, and its important for the squad. Hes also scored many penalties. Always its important to keep him at a good physical level, Puel added.But I hope other players can score also. Its important other players have the possibility to score: offensive midfielders, defenders from free-kicks. We have a statistic: we are third (in) the number of chances every game, and the least efficient. Free-scoring Liverpool will visit St Marys on Saturday Puel added that he expects to have a fairly fit squad to select from for the visit of the leaders.We will see in the last training session before the game, he said.I think all the players are okay and there wont be any surprises. Cedric has come back to training, [Ryan] Bertrand trained yesterday also.Shane Long also came back to training but I dont know if they are physically ready to play. We will see on Friday.Dusan Tadic suffered a suspected broken nose while in action for Serbia against Wales last weekend but is expected to play with a face mask.Normally he will be available for this game, Puel said. He spoke to the doctor and its OK for him.Goalkeeper Fraser Forster withdrew from the England squad with a slight injury but has been passed fit to line up against the Reds.Upgrade to Sky Sports now to watch Man Utd v Arsenal this Saturday and get the first six months half price! Also See: Mersons predictions Rodriguez: We deserve better Premier League questions How did your internationals do? ' ' '