This summer, ESPN.com is taking a closer look at each scholarship player on the Oklahoma Sooners' roster in our Crimson Countdown series. Each day, we analyze each player’s impact on the program since arriving on campus, his potential impact this fall, and his long-term projection. Starting with No. 1 Dominique Alexander, the series follows the roster numerically through No. 98 Chuka Ndulue.

No. 97 Charles Walker, defensive tackle, 6-foot-2, 296 pounds, redshirt freshman

Impact thus far: Walker hasn’t made an impact on the field but did create a buzz during his redshirt season and this offseason. If his production can match the hype, the Sooners will be thrilled.

Impact in 2014: Walker is one reason veterans like Torrea Peterson and Quincy Russell will have to raise their games if they want to earn a spot in OU’s defensive plans. It would be a surprise to see him force his way into a major role but he should be a contributor in his redshirt freshman season.

Long-term upside: It’s early to say but he has exceptional talent so fulfilling his upside would mean emerging as a major force for the Sooners during his career.

Evaluation grade for Walker: B. The only reason this grade is not an A is because Walker has not done anything on the field yet. All other signs point to an exceptional evaluation as he appears poised to make an impact as a redshirt freshman, yet his other offers were New Mexico, Houston and others. He looks like a hidden gem who was unearthed by OU.

Development grade for Walker: A. A redshirt season was perfect for Walker, who needed the time to adjust to playing defensive tackle in the Big 12 after lining up at several positions in high school. Thanks to a year of seasoning, Walker should be better prepared to help the Sooners this fall.