The Los Angeles Rams' coaching staff and roster underwent numerous changes throughout the offseason as star running back Todd Gurley was cut, receiver Brandin Cooks traded and three new coordinators arrived. But there was one group that went largely untouched: the offensive line.

After an uneven season, it was widely expected that the position group would be addressed in free agency, or more likely -- because of salary-cap constraints -- the NFL draft. But the lone addition came in the form of a seventh-round offensive guard.

Rams general manager Les Snead said he knew the lack of movement within the group would buck conventional thinking.

"We did go into [the draft] probably a little different than maybe the outside of our building where, 'OK, hey, it's a major, major glaring weakness,'" Snead said. "We felt confident that if we continue grooming and developing these players, they'd have a chance to become a really solid offensive line."

Since Sean McVay joined the Rams as coach in 2017, the Rams have used six of 39 draft picks to select offensive linemen, all of whom remain on the roster. And all 13 linemen (including practice-squad players) from last season's 9-7 team will return in 2020, including left tackle Andrew Whitworth -- who signed a new three-year, $30 million contract -- and guard/center Austin Blythe, who returns on a fresh one-year, $3.9 million deal.

"We know we have players that can play, but it's about finding ways to get the best five on there," McVay said. "Certain guys might have a little bit more position flex."

After the Rams held a virtual offseason program amid the coronavirus pandemic, it remains uncertain who will make the starting five, and how they will line up.

Whitworth, who is entering his 15th season, will maintain his post at left tackle. After an unexpected decline in production last season, Rob Havenstein -- who was sidelined after nine games because of a knee injury -- is anticipated to return to right tackle. Blythe, a dependable starter at center and guard, also is expected to maintain a starting role.

"I'm still comfortable going back and forth," Blythe said. "Wherever the team thinks that I can help the best or help the most is a position that I'll play."

Last season, the Rams' line experienced instability previously unseen in McVay's tenure as coach.

In 2017, the Rams started the same five linemen in 15 games (McVay did not play starters in Week 17). In 2018, the Rams started the same five linemen every game as they powered their way to a Super Bowl LIII appearance.

But last season, the offensive line shuffled through five different starting lineups because of injuries and fit issues.

As the Rams drew 118 penalties in 2019, which ranked 25th in the NFL, 42 of those penalties were committed by the offensive line -- including 13 from Whitworth and eight from Havenstein.

The offensive line's pass block win rate dropped from 74.3% in 2018 to 56.9% last season, according to ESPN metrics powered by NFL Next Gen Stats.

McVay and Snead have emphasized that the unanticipated injuries and growing pains last season could pay dividends in 2020.

"We've been adding those players and I've said it many a times," Snead said. "Fortunately or unfortunately, a lot of them got to play last year."

Whitworth emphasized the unit's steady growth through the final seven games after the lineup stabilized.

"You really think about the inexperience we had up front and how little guys have played in football games," said Whitworth, who played alongside four left guards during 2019. "To see where we finished the season offensively and really were able to build ourselves up."

If optimism about the development of the offensive line pans out, the Rams' biggest issue next season could be sorting which players will fill interior spots.

Guard Joe Noteboom and center Brian Allen, who started a combined 15 games in 2019, return from season-ending knee injuries. Guard David Edwards and tackle Bobby Evans -- who both were thrust into starting roles as rookies -- and guard Austin Corbett, who started seven games last season, also will compete for starting spots.

"We have a lot of guys who can play really good football," Blythe said. "When you have guys go down to injury like we did last year, there are silver linings to all of it."