Johnson started the summer at fourth on the depth chart and has worked his way up to sharing the back up job behind Mike James with Eduardo Clements. Johnson was one of the top RB prospects in the nation coming out of high school. As a senior, he ran for more than 2,000 yards and average 10 yards a carry.
Here is a look at how Johnson's junior season could play out:
Why he'll flourish: Johnson's speed -- he's rumored to have posted a 4.3 time in the 40 -- has produced plenty of big plays in preseason. He took a screen pass 37 yards for a touchdown and has reached the end zone five times in two scrimmages. He may not unseat James as the starter, but he'll be an outstanding change-of-pace.
Why he'll struggle: James isn't giving up his job easily. He's scored four times in the two scrimmages, including a 51-yard run. At 5-9 and just over 180 pounds, Johnson may find it harder to run between the tackles in college, where the defenders are bigger and faster than in high school.
NFL outlook: Obviously, it's premature to slot Johnson's draft position before he's taken a snap that counts in college. If he can add bulk without sacrificing speed and prove that he's durable enough to take the pounding on inside runs, Johnson could be an early pick by the time he's eligible to be drafted.
Projected 2012 stat line: 600 rushing yards, 400 receiving yards, five touchdowns.
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