Hall of Fame receiver Jerry Rice this week suggested that the San Francisco 49ers should join the lineup of suitors for Peyton Manning, and it's an interesting idea.

But it's not a good one.

Hiring Manning would mean tearing up your offense, and, frankly, I don't know that Jim Harbaugh is up for that. But let's go a step farther: Hiring Manning would mean junking quarterback Alex Smith, and I went down this road before with Baltimore in 2001 when the Ravens jettisoned Super Bowl quarterback Trent Dilfer for Elvis Grbac.

Now before we go farther let's get something straight: I'm not trying to equate Grbac to Manning. But at this point of his career I don't know what Manning has left. At least Grbac wasn't hurt, was a Pro Bowl quarterback and was in the prime of his career.

The Ravens' move to Grbac made sense because Baltimore upgraded the quarterback position with a more accurate quarterback. Except they sacrificed chemistry when they lost Dilfer. And they were never the same.

That could happen in San Francisco, too. I know, Smith isn't Peyton Manning --- or what Peyton Manning was in 2010 -- but he was good enough last season to lead the 49ers to a division championship and finish second to Matt Stafford in the league's Comeback Player of the Year award.

Smith was perfect for the 49ers, a guy who, like Dilfer, didn't make mistakes, was capable of making big plays and knew how to win.

But there's something else. Alex Smith took the 49ers to the conference championship game, and he did it with last-minute heroics in the divisional playoff s. New Orleans. So the 49ers didn't beat the New York Giants. That wasn't Alex Smith's fault. Last time I checked San Francisco would've made it to Super Bowl XLVI were it not for a couple of Kyle Williams' gaffes on punt returns.

Granted, Smith wasn't terrific in that game. But that could happen against the Giants. Look how Matt Ryan played against them. Or Aaron Rodgers. The two combined for 20 points, for crying out loud.

Alex Smith fits a niche that is perfect for San Francisco. So don't screw it up.