Johnson is a fifth-year player who didn't start for Kansas until his senior year. He was a former walk-on who worked his way to a scholarship; his key attributes as an NFL prospect are competitiveness and smarts. Johnson makes up for athletic hitches in his play by keying into the offense and flying around at top speed. He could get drafted late, but regardless stands a shot to make a roster as an immediate special teams contributor.
Johnson has good instincts to get his body to the ball. He has an ability to read blocking schemes and work to fill his gaps. He meets opposing offensive linemen with leverage so that he can maintain his run responsibilities and stay active in the play. He keeps blockers away from him both high, by using his hands, and at his feet, by bending down. He is a strong player who gets a lot of production by keeping blockers off him and understanding where they're coming from, a trait highly attractive to coaches of 3-4 schemes.
Johnson will have to overcome the perception that he isn't physically talented enough to make it at the next level. There are various aspects to his game where he struggles, mainly in pass coverage. In both man-to-man and zone coverages, Johnson could have his athletic ability exploited in space. He doesn't have the speed, footwork, or hip fluidity to cover some of the more athletic players at the next level. He will have to be drafted within a particular scheme that fits his needs in order to find success early.
Future Hall of Famer
A once-in-a-generation type prospect who could change how his position is played
An impact player with the ability/intangibles to become a Pro Bowl player. Expect to start immediately except in a unique situation (i.e. behind a veteran starter).
A quality player who will contribute to the team early on and is expected to develop into a starter. A reliable player who brings value to the position.
A prospect with the ability to make team as a backup/role player. Needs to be a special teams contributor at applicable positions. Players in the high range of this category might have long-term potential.
A player with solid measurables, intangibles, college achievements, or a developing skill that warrants an opportunity in an NFL camp. In the right situation, he could earn a place on a 53-man roster, but most likely will be a practice squad player or a camp body.