STILLWATER — Oklahoma State’s spring football practice is winding down, so it’s the perfect time to take a look at how the Cowboy defense has progressed this spring. "We feel good about where we are,” defensive coordinator Bill Young said last week. "But you always want to be better than you are.” Here’s a closer look at the Pokes’ defensive question marks heading into the spring and the progress toward addressing those concerns. →Defensive tackle depth. Young is content with OSU’s three-tackle rotation of seniors Shane Jarka and Chris Donaldson along with sophomore Nigel Nicholas. But the Cowboys’ lack of a fourth tackle, and the position overall, was arguably OSU’s top concern overall this spring. Sophomore Cooper Bassett is the early answer as a fourth defensive tackle. The former Tuttle star has made a remarkably quick transition to the defensive side of the ball, first at end and now at tackle. "Cooper Bassett has really stepped up,” Young said. "We are proud of the way he is performing right now.” →Find a replacement for Andre Sexton at "Star” linebacker. The "Star” position is one of the keys to Young’s defensive system. It requires a player who can be physical in the running game yet match up one-on-one with receivers in the passing game. Fortunately for Young and the Cowboys, freshman Joe Mitchell has been one of the spring standouts and looks poised to make an impact, if not start, at "Star” linebacker in the fall. Young said replacing Sexton could end up being more of a "by committee” situation. A safety or cornerback could fill the spot on passing downs, and redshirt freshman linebacker LeRon Furr filling the spot in short yardage situations. →Replacing Perrish Cox and Terrance Anderson at cornerback. Sophomore Brodrick Brown has stepped up this spring and looks like he has secured a starting spot heading into fall camp. He replaced the suspended Cox as the starter for the Cotton Bowl. "The Cotton Bowl was tremendous for him,” said cornerbacks coach Jason Jones. "He got thrown in with both feet and played well. He’s been the most consistent cornerback this spring.” Fellow sophomore Andrae May entered spring as the other starter, and he’s maintained his spot. True freshman Devin Hedgepeth has impressed early with his intelligence and dependability. Sophomore junior-college transfer Malcolm Murray has had his ups and downs but has impressive athletic ability. "He’s coming along,” Jones said of Murray. "He’s not full speed because he’s thinking before he reacts, so he’s playing slow right now.” While the Cowboys made progress this spring, several incoming freshman defenders, including linebacker Shaun Lewis and cornerback Justin Gilbert, likely will be counted on to play immediately and provide additional depth.