By Steve Silverman-

(CBS) The San Francisco 49ers have moved to the top of the power rankings around the league and are starting to look like they can fill the preseason expectations that had them as the favorite to win the Super Bowl this year.

The current story line with the Niners is head coach Jim Harbaugh’s decision to give Colin Kaepernick the starting quarterback position over Alex Smith. It’s a gutsy move, but it could prove a bit premature.

Kaepernick has been brilliant in wins over the Bears and Saints, but he’s not quite ready for Hall of Fame enshrinement.

And if you study his situation a little deeper, you will see that both Kaepernick and Smith have an advantage that few of the other NFC contenders have at their disposal: A stellar offensive line.

The 49ers are starting to dominate right now and their powerful offensive line has as much to do with it as their quarterback play.

Harbaugh has five excellent starters on his offensive line and the 49ers have the ability to crush opponents with a downhill running game.

Much of the credit goes to Frank Gore, who may be the most honest player in the league. I have no idea whether Gore is sincere when he tells his anecdotes in the locker room, but no player gives more of himself on an every-play basis.

Gore knows that he is going to get overpowering blocking from left tackle Joe Staley, left guard Mike Iupati, center Jonathan Goodwin, right guard Alex Boone and right tackle Anthony Davis.

Hall of Fame quarterback and three-time Super Bowl winner Troy Aikman has said that the San Francisco offensive line is the best he has seen in the NFL since the line that protected him during his career with the Cowboys was operating at peak efficiency.

Aikman said that he doesn’t think any other team is close to the 49ers when it comes to offensive line proficiency.

All of the Niners offensive linemen are nasty maulers, but when they run plays behind their vaunted left side with Staley and Iupati, they are basically unstoppable.

The Bears intend to challenge the Niners if they ever get another shot at them in the postseason. While the Bears can play a better defensive game than they did in that Week 11 32-7 Monday night loss, just how is the beleaguered offensive line supposed to hold up against Aldon Smith & Co?

The only dependable offensive lineman the Bears have at this point is center Roberto Garza. Guard Lance Louis is done for the year with a torn ACL, Chris Spencer has a knee injury and Chilo Rachal is off in never-never land.

The Bears are hoping to help out their damaged interior line by bringing in Andre Gurode, the former Pro Bowler who has not played at all this season.

Jonathan Scott and J’Marcus Webb man the tackle spots and the Bears are now just hoping that Edwin Williams can hold his own at guard.

Every other NFC contending team has issues on the offensive line. The Giants have always prided themselves on their ability to dominate with their offensive line, but two of their best blockers have been slowed by shoulder injuries. Center David Baas and right tackle David Diehl can’t drive into opposing defensive linemen and linebackers. Of the two, Diehl is in worse shape and it could be difficult for him to finish the season.

The Packers need stellar offensive line play to protect Aaron Rodgers because they have no running game. Alex Green and Cedric Benson could not produce for them even if the seven blocks of granite were blocking for him.

But Rodgers has not been getting pristine protection. He was under the gun against the Giants and huge left tackle Marshall Newhouse is one of the primary reasons for Rodgers’ duress. Newhouse is too slow to block decent pass rushers.

Packers wide receiver James Jones put it squarely on the offensive line this week.

“There’s really no way around it. Guys are open,” Jones told the Milwaukee Journal Sentinel. “It’s just a fact of us protecting Aaron, keeping him in the pocket. Keeping him confident in the pocket where he doesn’t have to run every other play and then try to make a throw on the run. Guys are open, man.”

Even the 10-1 Atlanta Falcons have issues with their offensive line. Matt Ryan has been having a sensational season, but that’s because he can complete passes on the run. Falcons left tackle Sam Baker is an athlete who can move his feet, but he is not physical. Neither is left guard Justin Blalock.

The 49ers have an advantage over all the legitimate contenders on the offensive line. The Giants may be close, but the others all have too many issues to get close before the postseason begins.

steve silverman small Silverman: Offensive Line Issues Hit All NFC Contenders Except 49ers

Steve Silverman

Steve Silverman is an award-winning writer, covering sports since 1980. Silverman was with Pro Football Weekly for 10 years and his byline has appeared in the Wall Street Journal, Playboy, and The Sporting News. He is the author of four books, including Who’s Better, Who’s Best in Football — The Top 60 Players of All-Time. Follow him on Twitter (@profootballboy) and read more of his CBS Chicago columns here.

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