With their third pick in the fourth round, the San Diego Chargers selected Running Back Gartrell Johnson. He looks to have done most of his work in his senior year and stands 5'10", 119 pounds. The Bleacher report has a nice write up on the pick.

Overall Football Traits
Production12004: Johnson sustains season-ending injury in season opener against Minnesota and he receives a medical red shirt. He rushes for a total of 12 yards on two carries and catches one pass for a loss of two yards. 2005: Johnson appears in three games rushing for a 26 yards on 11 carries. 2006: Johnson starts seven of the 12 games he appears in rushing for a total of 305 yards and six touchdowns on 109 carries. He catches five passes for a total of 51 yards. 2007: Johnson starts seven of the 12 games he appears in rushing for a total of 957 yards and six touchdowns on 181 carries. He catches 12 passes for a total of 103 yards and two touchdowns. Johnson primarily lines up at fullback during first five games of season. 2008: Johnson starts all 13 games rushing for a total of 1,476 yards and 12 touchdowns on 278 carries. He catches 32 passes for a total of 295 yards.
Height-Weight-Speed4Adequate height and prototypical bulk but top-end speed is marginal at best.
Durability42007: Leaves Wyoming game with ankle injury in the third quarter and doesn't return. 2004: Sustains season-ending injury in the season opener.
Character2Team leader.
Running Back specific Traits
Competitiveness2Downhill runner that keeps churning legs on contact and almost always falls forward. Runs hard but doesn't always get knees up and has some problems stepping out of shoestring tackles. Appears to take pride in blocking and doesn't shy away form contact.
Vision3Does an adequate job of using lead blocker and reading the flow of linebackers when runs inside but frequently takes too long to locate a seam and turn upfield when running outside.
Explosiveness3Can hit second level going full speed when runs inside but lacks ideal initial quickness and going to have a harder time turning the corner at the NFL level. Lacks breakaway speed and isn't much of a homerun threat.
Balance/Change-of-Directions3Makes crisp first cut and can cutback but lacks ideal elusiveness and isn't going to make many defenders miss in the open field.
Passing Game3Willing pass blocker who can step up and stop blitzing linebackers/safeties in their tracks but doesn't always get into sound position. Isn't fast enough to run by NFL linebackers on wheel routes. Looks ball in but traps it against frame a little too much and prone to dropping passes should catch.