Rams, 49ers and why they're so different

The preseason NFC West favorite St. Louis Rams take a 2-9 record into Candlestick Park on Sunday.

They will not take their starting offensive tackles or their leading receiver from 2010, and to hear coach Steve Spagnuolo tell it, injuries help explain why the Rams haven't kept pace with the 9-2 San Francisco 49ers this season.

2011 49ers-Rams Offenses

Spagnuolo, speaking to reporters covering the 49ers, said injuries are no excuse. He also said continuity is crucial for teams installing new offenses, as the Rams and 49ers did this season. He said that was especially so coming out of a lockout-shortened offseason.

"We knew there'd be some rough edges, but you'd hope that you'd get to this certain point of the season and those reps underneath your belt would surface and you'd have some success," Spagnuolo said. "I think that’s happened for San Francisco."

The 49ers averaged 213 yards per game over the first three weeks of the season, never exceeding 226. They have averaged 344 yards over the subsequent eight games, despite a season-low 170 during their most recent game, a 16-6 defeat at Baltimore.

"You have a better chance of doing that when you can keep the same the same 11, 12, 13 guys on offense," Spagnuolo said. "We haven’t had that, and again, as a professional football team, professional coaches, professional players, you have to find a way to overcome that and it’s been tough for us to do that."

The Rams averaged 279 yards over their first four games, 349 over their next four, but only 246 over their past three. They are in decline.

St. Louis' offense suffered more significant injuries early in the season. The quadriceps injury Steven Jackson suffered in Week 1 sidelined him for one game and limited him for weeks. Losing 2010 receiving leader Danny Amendola at the same time compounded the problems.

The Rams' preferred personnel group -- Jackson, Brandon Gibson, Amendola, Mike Hoomanawanui and Lance Kendricks -- never played a snap together. The team acquired Brandon Lloyd by trade, explaining why the chart lists 12 projected starters for the Rams. But with Hoomanawanui suffering from injuries before ultimately landing on injured reserve, and with quarterback Sam Bradford missing time with an ankle injury, continuity suffered badly.

The 49ers' preferred offensive personnel group -- Frank Gore, Michael Crabtree, Josh Morgan, Vernon Davis and Delanie Walker -- played extensively together until Morgan's season-ending injury in Week 5. The remaining four continue to play extensively together. Their quarterback, Alex Smith, hasn't lost a snap to injury.

The injury Bradford suffered at Green Bay on the final offensive play in Week 6 came just as the offense had amassed a season-high 424 yards, only to lose 24-3. That injury was a tough setback, but the team won for the first time all season two weeks later -- with backup A.J. Feeley at quarterback against New Orleans.

2011 49ers vs. Rams

Injuries are not the only reason for the disparity between St. Louis and San Francisco. They might not be the primary reason.

The 49ers' defense and special teams have taken pressure off their offense. Their offense has made great use of favorable field position. Their offensive line has struggled at times, but the 49ers have developed a power running game the Rams never matched even before injuries undercut their line (Jackson's production largely came on misdirection-type runs from shotgun formations). The Rams' defense has also fallen far short of expectations, buckling against the run in particular.

The 49ers have nearly doubled the Rams in scoring (262-140) despite averaging only 13.1 additional yards per game. Both teams are converting around 30 percent of the time on third down. They average right around 4.2 yards per rushing attempt. The Rams have a slightly lower interception rate.

Both teams have lost starting or primary wide receivers to season-ending injuries. The Rams counted on Amendola more than the 49ers counted on Morgan. But as valuable as Amendola was to the Rams -- he caught 85 passes last season, compared to 44 for Morgan -- the season did not hinge on his availability.

By my count, eight projected Rams starters on offense have missed a combined 25 starts, while two projected 49ers starters have missed a combined eight starts. I've used the word "projected" because those totals reflect only players projected as starters coming into the season. The breakdowns fall this way:

  • Rams: Amendola 10, right tackle Jason Smith 5, tight end Hoomanawanui 3, Bradford 2, left tackle Rodger Saffold 2, Jackson 1, receiver Gibson 1, tight end Kendricks 1.

  • 49ers: Morgan 6, Crabtree 2.

I did not consider fullbacks as starters because both teams' preferred groupings featured a halfback with two tight ends. The 49ers have played most of the season without veteran fullback Moran Norris, but Bruce Miller has grown into the role. The Rams have occasionally started fullback Brit Miller.

Both teams made performance-related changes to their offensive lines. The 49ers benched right guard Chilo Rachal after three games. The Rams benched center Jason Brown more recently.

Injuries have wiped out the Rams' offensive line in recent weeks, but their five projected starters were in the lineup into Week 7, with disappointing results. The 49ers were 5-1 at that point. The Rams were 0-6. Those trends have pretty much held.

Spagnuolo's comments covered the offense. The Rams' problems on defense are a subject for another conversation.