Before: Joe Staley, Mike Iupati, Jonathan Goodwin, Adam Snyder, Anthony Davis, Alex Boone, Chilo Rachal, Daniel Kilgore and Mike Person.
Why: LT Joe Staley was a Pro Bowler and LG Mike Iupati was very good, but the mere presence of RG Chilo Rachal in the starting lineup at the beginning of the season nearly sunk the entire offense. Harbaugh benched him for Adam Snyder, who upgraded the right guard position from abominable to just below average, which was important. The young and athletic right tackle Anthony Davis got beat for sacks left and right the first half of the season, but improved as he went along.
Now: Subtract Adam Snyder and Chilo Rachal. Add Joe Looney and Jason Slowey.
Why: Trent Baalke traded up in the fifth round last year to draft Daniel Kilgore, who will most likely start at right guard. He’s stronger than Snyder, and he has quicker feet, which means he should be a better run and pass blocker. The Niners gave up a lot of sacks right up the middle last season, so Kilgore should be able help Goodwin pass protect on the interior better than Snyder did. Anthony Davis should continue to improve as well – he might actually become a good right tackle this year. If the 34-year old center (Goodwin) slows down this season, Kilgore could slide over to center and the Joe Looney, the Niners fourth round pick this year – a guy they’re wild about – could play right guard, too. This is a solid offensive line, but it’s a tad young and inexperienced, and that’s why it’s a “B.”