In his own words, Matt Birk "can only imagine" what Andre Gurode
must be going through.  Gurode, a five-time Pro Bowler at center
between 2006 and 2010 when he was a member of the Dallas
Cowboys, is preparing to possibly start at right guard for the
injured Marshal Yanda when the Ravens visit the Cincinnati
Bengals in the teams' regular-season finale on Sunday.  Birk,
the starting center since joining the team prior to the 2009
campaign, smiled when asked about the difficulty in Gurode's
assignment.  "I can only imagine because, luckily, I've only
been a center for a long time, and I haven't had to move," Birk
said. "It doesn't seem like much, probably, to anyone on the
outside, but the mechanics of everything, just starting with the
stance, it's so different from snapping the ball. You're more
off the ball at guard, different type of techniques, different
type of players in terms of three-techniques [defensive tackles
who line up on the outside shoulders of guards] versus nose
guards. So from the outside, it