Rams' defense might be even more vulnerable

Posted by ESPN.com's Mike Sando

The Rams have allowed 35.75 points and 181.25 rushing yards per game to their last four opponents. They will try to improve against the Dolphins in Week 13 with seventh-round rookie David Vobora taking over at middle linebacker and wearing the radio headset.

If you're going to lose badly, you might as well evaluate younger players. The Rams are taking that approach in part because they have few options. Starting middle linebacker Will Witherspoon remains limited by injury. Versatile veteran Chris Draft could miss another game while recovering from a broken foot.

The Rams lack depth at linebacker even with Witherspoon and Draft. They allowed 340 yards rushing to the Titans when Witherspoon missed an exhibition game. They will now face a team built in the image of Dolphins vice president Bill Parcells. The Dolphins have exceeded 150 yards rushing four times this season. They had 222 against the Raiders in Week 11.

The Rams made Vobora the final choice of the 2008 draft. "Mr. Irrelevant" figures to become very relevant within the Dolphins' offensive game plan.