The Rams, in search of their first winning season since 2003, also are breaking in a new offensive coordinator. The defense returns virtually intact.
Players gathered Monday for strength and conditioning with no field work. Tight end Jared Cook said it was like ''the first day of school.''
''You come in with a fresh new outfit, fresh new shoes. Spider-Man lunch box, you're showing off your new stuff,'' Cook joked. ''Naw, it's just guys getting acclimated again.''
It's anticipated the playbook won't change dramatically under Frank Cignetti, who had been the quarterbacks coach before Brian Schottenheimer left for the coordinator job at Georgia.
Cignetti's familiarity with the roster figures to be a plus. Cook said 80 percent of the playbook is in but wouldn't give up any secrets.
''If we would have gotten a totally new offensive coordinator, there ain't no telling what changes he would have brought that would have confused everybody,'' Cook said. ''The coaches have been working diligently to get this stuff in, so now is our time to learn. No, you can't have a preview.''
Generally speaking, he wouldn't characterize the scheme as simplified, either.
''You're here to do your job, so do your job,'' Cook said. ''No matter what you have to do to learn it, you learn it.''
Many players were taken aback by the Bradford trade to Philadelphia in February. Coach Jeff Fisher had said several times that Bradford was his quarterback, but an agreement on a restructured deal could not be reached.
''Sam's a good friend of mine, so whenever you lose friends on the team, there's that aspect of it where you're still human,'' middle linebacker James Laurinaitis said. ''You miss your friends. I was friends with Jake Long, friends with Chris Wells.
''Heck, one of my closest friends being here was Josh Hull and he ain't here anymore, either.''
Now, they're getting acquainted with Foles.
''Just kind of a fan of the way he plays the game, how he's picked up the offense,'' Cook said. ''I just admire the way he slings the ball around.''
Added Laurinaitis: ''I would like to have a QB for all 16 games, no matter who it is.''
There's little turnover on defense. Tackle Nick Fairley gives the line five former first-round picks and Akeem Ayers adds depth at linebacker. Ayers had four sacks and an interception in nine games with New England, and Fairley, who slumped last year, combined for 11 1-2 sacks in 2012 and '13.
''It's very rare, and it's exciting,'' Laurinaitis said. ''When you have five first-round D-linemen, it makes your short yardage a lot better, your goal line a lot better.''
Players aren't wasting time fretting over the possibility of a franchise move back to Los Angeles after this season, either.
''Look, everybody can sit here and talk about it but the truth is it's out of everybody's hands except for one guy or a couple of guys on the other party,'' Cook said. ''All this stadium talk on both ends, it all sounds good, but really what can you do about it?''
When he was a boy, Laurinatis was taught not to worry about something that's out of your control.
''There's a lot of things in life I can worry about that I can control,'' Laurinaitis said. ''I can't control whether we go, whether we stay. All I know is for this season we'll be playing in St. Louis and there will be big expectations.''
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