San Francisco 49ers Mock Draft 2012 (with QB Peyton Manning)

This is a needs-based NFL draft. So was the last one. But the San Francisco 49ers have brought back the great defense, grabbed "the" quarterback (assuming Manning signs) and now must address the offense (mostly).

The 49ers need a fix at guard (Adam Snyder & Chilo Rachal are now gone). The 49ers also need a backup at center. Jonathan Goodwin was banged up this year and Chase Beeler is not enough of a talent for Manning.  

But a guard or center in Round 1? DeCastro, Glenn and Konz will be gone, so probably not.

They do have enough receivers with Michael Crabtree, Randy Moss, Mario Manningham, Kyle Williams, John Matthews, Joe Hastings and Dontavia Bogan. Tight end seems to be set with Vernon Davis, Delanie Walker, Nate Byham and Konrad Reuland.

Frank Gore, Kendall Hunter, Anthony Dixon and the new addition of Rock Cartwright set the running backs. So what other offensive position rates a first round? Try offensive tackle.

Offensive Tackle Mike Adams from Ohio State is the pick. He can spell Davis or Joe Staley. Alex Boone, Derek Hall, Kenny Wiggins and Mike Person are good backups. But Adams can start in the event of injury. The Rams will be after Adams with the 34th pick overall.

After Mike Adams, the 49ers Absolutely Need to Acquire a Guard

With Mike Adams providing a third decent tackle, the Niners must continue to fix the O-Line.

There is only one quality starting guard on the team. With Snyder and Rachal gone, Daniel Kilgore was a fifth-rounder out of Appalachian State who is considered a backup. 

So where is the starter at right guard?

He is the second=round pick: Kevin Zeitler from Wisconsin. At 6'4" and 315 lbs, Kevin can boast a few accolades. First-team All-American by AFCA and Pro Football Weekly. Second-team All-American by Yahoo! Sports and Phil Steele. Consensus first-team All-Big Ten. And he is smart with an Academic All-Big Ten title.

If Kevin is not available, Kelechi Osemele or Amini Silatolu would be good alternates in the second round.

With a Decent Right Guard, Here Is a Good Backup at Center

Oh yes, the 49ers will truly protect their investment at quarterback with a third consecutive pick for the offensive line.

And that will be a decent backup to fifth-rounder Jonathan Goodwin. Chase Beeler is a pretty good free-agent center; however, the Niners need to find a future starter to replace Goodwin. Beeler is not that guy. 

There are actually a few centers that can do the job here and are all third-rounders. Ben Jones from Georgia, Phillip Blake from Baylor and Mike Brewster from Ohio State.

All should be available; however, Ben Jones is arguably the best of the three.

The First Three Were Offense, Time for a Defensive Player

Even though the 49ers brought back the top defense in the league, complete with Carlos Rogers at cornerback, they still need a decent player at corner.

The challenge here is that Morris Claiborne, Janoris Jenkins, Dre Kirkpatrick, Stephon Gilmore, Jayron Hosley, Alfonzo Dennard, Trumaine Johnson, Brandon Boykin, Chase Minnifield, Robinson, Leonard Johnson, and maybe Casey Hayward will all be picked. '

The 49ers could go with the next proven talent like Coryell Judie from Texas A&M, but a better gamble with the 126th overall pick would be to gamble on Omar Bolden, cornerback from Arizona State, or Cliff Harris, cornerback from Oregon.

Bolden is recovering from a torn ACL, but was previously predicted to be a top-10 pick by some analysts. He is worth the risk. Harris was set to be a top-five pick in this year's draft, but he was suspended at Oregon and his stock plummeted. He is also worth a gamble here. 

A Gamble in the Fourth Round Deserves a Gamble in the Fifth Round

Using the fourth round to grab a potential first-round corner deserves a gamble in the fifth for another top wide receiver.

Oklahoma's Ryan Broyles led so many receiving categories in the nation before his torn ACL. Ohio State's DeVier Posey was also a top receiver coming into last season, until he was suspended for making selling a jersey and making too much money in a summer job.

But what a receiver for the fifth round either would be. Both could have been picked in the first round this year before adversity struck. Either would be a great gamble for a backup wide receiver position.

The Defense Is Great, but a Free Safety Would Help the Team

A free safety in the sixth round would benefit the team. This is a position of need.

In the sixth round, the free safeties are just starting to come off the board. The top two or three might be gone, but Tramain Thomas from Arkansas and Tysyn Hartman from Kansas State should be available.

Thomas would be the pick here, but Hartman is a very good alternative.

The Fullbacks Haven't Been Raided Yet in the Seventh Round

Yes, the 49ers need a fullback. They let Moran Norris go. 

Bruce Miller has been hampered with some injuries and there is no backup.

There will only be one or two picked by the seventh round. Fullbacks are the last to go.

Chad Diehl from Clemson and Brad Smelley from Alabama will both be on the board. They are the third- and fourth-ranked fullbacks in the country.