I reached out to the folks at SB Nation's Chargers blog, Bolts From The Blue, for the low-down on Johnson. Here's what I got from John, who goes by the intriguing screen name 'obviousman.' I think it's an honest, intriguing assessment.
OK, well let me start off by saying I was a big Gartrell Johnson fan. Anyone who saw his bowl game against Fresno State would be, and I watched it live. Here's as good of a scouting report as I can give on Gartrell:
Gartrell is a power back, through and through. Or at least he will be one some day. The Chargers were holding onto him because they loved his potential, but he really needs to learn to stay low after first contact. Too often he would hit somebody (sometimes his own lineman) and get stood up, then immediately get taken down. His size also makes him less-than-ideal for the power back spot, but the kid runs with strength and hits with violence.
There are negatives in his game though. For one, he has zero speed. I doubt he ever takes a carry for more than 15 yards in his entire NFL career. There were two instances in the preseason where he had nobody in front of him and was caught from behind easily by a LB. The second flaw is patience, which isn't rare for a rookie. He has a hard time waiting for the hole to develop, partly because he's almost at full-speed when he gets the ball (I loved that about him), and can ruin plays that way.
If Gartrell can become more patient and stay low to the ground, he has a real future as a goal-line back in the NFL. He wasn't cut because of anything he did, but rather because the Chargers need bodies for all of the injuries that are stacking up on both lines. Also, Michael Bennett completely and totally outperformed Gartrell in the pre-season.
He's a good project back to have on the roster, and with an O-line like the Giants have he could be an effective goal-line back this season. However, he will never be Jacobs, Bradshaw or even [Derrick] Ward.
Johnson ran for 184 yards on 48 carries (3.8 yards per carry) and caught seven passes for 57 yards during the exhibition season.
Here's a pre-draft scouting report on the 5-foot-11, 218-pound rookie from Colorado State. It comes courtesy of SB Nation's fine draft blog, Mocking the Draft. By the way, the Chargers drafted Johnson in the fourth round.
Strengths: A powerfully built, one-cut running back, Johnson really came on during his senior season. Quick feet and has good agility. Great vision. Has a body that allows him to shake off tacklers. Runs with a good, wide base. Gets terrific body lean and could be good in short yardage plays.
Weaknesses: Does not have great speed. Doesn't have a great initial burst at the line of scrimmage, which can make it hard for him to quickly scoot through a hole. Not the best receiver out of the backfield. Needs to improve his hands and route running.
Final word: Johnson has an NFL-sized frame, but questions about his speed and quickness hitting the hole greatly limit his upside. A powerful running back, Johnson can break tackles and run over opponents.
Johnson was Colorado State University's leading rusher the past three years and last fall ran for 1,476 yards, the second-best total in school history, according to the Coloradoan.
Here is one more look at Johnson, a video from DraftGuysTV.
Sounds like a guy who might turn into another useful, under-the-rader "get" for GM Jerry Reese. Perhaps he will eventually help in short-yardage, where we know the Giants have issues.