From now until the start of free agency, on March 7, we'll take a position-by-position look at the Los Angeles Rams in eight installments. The Rams -- coming off a 4-12 season that prompted the hiring of rookie head coach Sean McVay -- have about $40 million in cap space but do not have a first-round pick. They also have a lot of needs, all of which can feel a little overwhelming without breaking it down by section. We'll do that here. Next up: the offensive line. (Previous: WR/TE, DL.)

If the Rams hope to improve their offensive line, the first step will likely be finding a left tackle to replace Greg Robinson, who has struggled at the position. G. Newman Lowrance/AP Photo

Key returnees: Greg Robinson, Rodger Saffold, Rob Havenstein, Tim Barnes, Jamon Brown, Cody Wichmann, Andrew Donnal

Notable free agents: N/A

Top free agents available (for now): Kevin Zeitler (G), Rick Wagner (RT), T.J. Lang (G), Andrew Whitworth (LT), Larry Warford (G), Riley Reiff (RT)

Key stat: The Rams' offensive line allowed 25 sacks of Jared Goff over the last six games, the most in the NFL during that stretch. That averages out to more than four sacks a game. Over the course of a full season, that rounds off to 67 sacks, which would have been the fourth-highest total in history. Only David Carr (76 with the Texans in 2002, 68 with the Texans in 2005) and Randall Cunningham (72 with the Eagles in 1986) absorbed more sacks in a season.

Was it scheme or talent? Did they draft the wrong players, or did they simply not develop them well enough? These are the questions the Rams must answer about their offensive line, which took a major step back in a season hindered mostly by an inability to protect the quarterback or open space for running back Todd Gurley. The Rams drafted seven offensive linemen from 2014 to '15, but none of them necessarily played well in 2016.

Their first step is to figure out what to do with Robinson, who has struggled mightily at left tackle since being drafted second overall in 2014. They could give him another shot at left tackle, this time under the direction of new offensive line coach Aaron Kromer, who replaces Paul Boudreau. They could also move him to guard, or release him outright.

That decision will set the tone for everything else. The strong likelihood is that the Rams will need a new left tackle, a position that could either be filled by Saffold or a free agent like Whitworth. But they also have to figure out why Havenstein, a second-round pick in 2015, seemed to fall off so dramatically in his second season. They also have to settle on a right guard, a position where Wichmann, Brown and Donnal all started in 2016. And they have to determine whether Barnes is the right fit at center.

McVay will probably implement some of the outside-zone concepts he initially inherited from Mike and Kyle Shanahan, but the Rams must improve their personnel in order to run it effectively.