This was from John Sickels scouting book in 2010:
Chris Johnson has some pop in his bat, but his unimpressive strike zone judgment holds his offense back. His OPS was just +3 percent in the Pacific Coast League last year, and he looked overmatched in his major league time, granted a 22 at-bat sample is tiny. On the positive side, he's a solid defender at third base, with decent range and a very strong throwing arm. I think Johnson can hit .250 with 15 homers as season in the majors, but his OBP would be below average and his overall production would be substandard for a corner player. Unless his plate discipline takes a huge leap forward, I think he's destined to bounce between Triple-A and the major league bench jobs. Grade C.