The St. Louis Rams have plucked players from the San Francisco 49ers in the past. They picked up LB Larry Grant and S Michael Lewis over the last two seasons, slotting both in as useful role players. This year, if free agency actually happens, they could land a much bigger fish out of the Bay: LB Manny Lawson.
In a post today, ESPN's NFC West blogger Mike Sando speculates that the 49ers probably wouldn't use the franchise tag to keep Lawson since it would make him one of the highest paid outside linebackers in the league and his pass rushing ability doesn't equate to that kind of money. The tag, again if it turns out to be legit in light of the CBA, would probably run about $10 million for linebackers.
If he does end up leaving the 49ers, Lawson might be a much better fit in a 4-3 defense. Lawson is a stud in coverage; that and his speed could be exactly what the Rams need to fill the huge gap they have on the weakside. Plus, there's always the extra motivation he'd have against his former team twice a year.
Lawson is probably the best 4-3 OLB on the free agent market, even though he's coming from a 3-4, which is why he could end up in free agency. Washington's Rocky McIntosh, another OLB who isn't the best fit in a 3-4, is another possibility. Lawson will be 27 this season; McIntosh will be 28.
If and when free agency arrives, keep an eye on both players.