Shaun Nixon has a knee injury that will likely result in a redshirt season for him, TCU coach Gary Patterson said.The freshman running back from Lake Travis suffered the injury in practice last week and will undergo surgery. If it s going to happen, you want it to happen early, Patterson said. Because now he s got an opportunity to be back before spring ball. Nixon was one of the gems of the 2014 recruiting class. Patterson said he had gained 15 pounds and not lost any speed. He was looking great, Patterson said. Sometimes things happen for a reason. Patterson said it was a non-contact injury. He made a cut. Nobody hit him, Patterson said. Made a cut and it went out. It was no contact. The injury leaves last year s leading rusher B.J. Catalon, Kyle Hicks, Aaron Green and Trevorris Johnson at the top of the depth chart. Patterson expressed confidence last week in all of the tailbacks.DE movesJunior college transfer Mike Tuaua became the starter at right defensive end Monday, Patterson said. And Josh Carraway, a sophomore defensive end from Flower Mound Marcus, has claimed a spot at left defensive end in place of James McFarland, who has been out with a hamstring injury. You have an opportunity to be more athletic at that position than we were a year ago, Patterson said, but added that the team will have to redevelop the knowledge and toughness missing with Jon Koontz s loss to graduation.Patterson also praised the work of reserves L.J. Collier, Chris Bradley and Casey McDermott Vai, who have gotten extra snaps with defensive tackle Tevin Lawson sitting because of a concussion last week.Patterson is not down on Terrell Lathan, who came out of the spring as the starter at right defensive end. Lathan has unbelievable potential, he said. He s going to make us better. Strength of the teamPatterson said the safeties are the strength of the team right now. They re the ones, out of all of them, that I ve been the happiest with, he said. Asked why, he replied: Depth, make the plays they re supposed to make, and they re very talented. Patterson said players like Derrick Kindred, Kenny Iloka and Sam Carter give the secondary a size dimension they didn t have a year ago. Just athletes, Patterson said. They re more 200-pound dudes instead of 170s. Patterson said Carter and Kindred have shown they can switch between strong and free safety.He also said Geoff Hooker has had a strong camp at safety and again pointed out the work of cornerbacks Nick Orr, Corry O Meally and Torrance Mosley.QB updatePatterson said quarterbacks Trevone Boykin and Matt Joeckel each have done good things, but sidestepped the question of whether either had separated themselves in the first week of practice. Both of them have had their moments, he said.The team wants to make a decision by Saturday, but again Patterson cautioned that the assignment could change. There s five weeks, three ballgames we have a long time of progression, he said. I ve been fired up about both their leadership. But the key is, what does the guy do on Saturday? Scrimmage reviewPatterson said there were about 70 plays in the scrimmage 18 for the 1s, 2s and 3s, plus some goal-line work on Saturday, and that cornerback Kevin White had an interception on a fade in the end zone. Defensively, we have to have an attention to detail, Patterson said. Little things as far as assignment-wise, we ve got to get better at. Patterson believes there is plenty of speed at the offensive skill positions. There won t be anybody faster on offense, skill-wise, he said. Baylor s fast. Those guys have people who are fast, but they re not going to be faster. We had guys open, and we didn t get it to them. The quarterbacks have got to do a better job of getting them the ball when we have plays. Another scrimmage is planned for Tuesday.