Time to produce: CB Trumaine Johnson

EARTH CITY, Mo. -- As the St. Louis Rams prepare to enter their third training camp under coach Jeff Fisher and staff, much will hinge on the ability of the team's many young players to turn potential into production. In this final week before camp officially begins, we take a look at some players who must take the next step either to preserve their jobs, help the team reach its first winning record since 2003 or, to the team's preference, both.

We finish this week-long series with cornerback Trumaine Johnson.

What he's done: With Cortland Finnegan struggling and dealing with injuries, Johnson officially moved into the starting lineup in 2013 after making a cameo appearance in the role near the end of his rookie season. Johnson has had his share of ups and downs, with some performances brimming with potential and some games in which he's struggled quite a bit, especially in coverage. In two years, Johnson has 97 tackles with five interceptions and a forced fumble. For what it's worth, Pro Football Focus marked Johnson down for a 74.5 passer rating against, including a 61.3 percent completion percentage at a rate of 11.4 yards per completion.

Why he must do more: Johnson's production in 2013 offered plenty of hope that he's on the verge of becoming a solid to good starting corner in the NFL. At 6-foot-2, 208 pounds, Johnson fits the bill of a modern corner capable of matching up with bigger receivers and playing more physical at the line of scrimmage. In fact, those characteristics could make him an ideal fit in new coordinator Gregg Williams' defense. Williams' aggressive approach should put Johnson in position to have more success. It would also serve Johnson well to be more consistent as a tackler in run support. The Rams gave Johnson and fellow corner Janoris Jenkins a vote of confidence by not investing in another possible starting outside corner in the draft or free agency. But they might not offer the same courtesy if the third-year corners don't take another step in the right direction in 2014.

Where he fits: Barring an unforeseen injury or complication, Johnson will be one of two starting corners alongside Jenkins this season. The Rams haven't mixed and matched corners on receivers under Fisher, though it will be interesting to see if that philosophy changes with Williams in charge of the defense. Either way, expect Johnson to get more chances to use his size and strength in press coverage more consistently and less of the "off" coverage that resulted in the aforementioned completion percentage and yards-per-completion rate.