As the NFL free agency period approaches, the San Francisco 49ers are preparing to upgrade this roster once again. Jim Harbaugh and this front office, led by general manager Trent Baalke, have been magicians in the offseason.

Not only is their message, "get better everyday," but they also know how to accomplish it.

Unfortunately, Rome was not built in a day and it may take a third offseason under the new regime to solidify the next Super Bowl-winning 49ers team.

The first step by San Francisco is to self-assess and sign their own players before diving into the free agent pool. There are a number of hot commodities on the market but don't expect the Niners to be Day 1 players.

According to Matt Maiocco of CSN Bay Area, the 49ers will reportedly make Dashon Goldson and Delanie Walker priorities.

But when examining positions of need, one of the glaring holes is once again at wide receiver. For this, the 49ers will need to look outside the organization for assistance, which means free agency or the NFL draft.

San Francisco needs a complement for WR Michael Crabtree, who emerged as top-tier receiving threat. The 49ers have plenty of slot receivers - what they need is a big-bodied speedster to replace the void inevitably left by Randy Moss and Ted Ginn Jr.

Let's take a look at some of the options San Francisco has in FA:

First-Tier

Greg Jennings, Mike Wallace and Dwayne Bowe

First of all, it is fairly unlikely that the 49ers pursue any of these top-tier receivers. The Niners had opportunities to bring in a big-time pass-catcher the past two seasons under the Harbaugh regime.

However, the team chose to pass on names like Vincent Jackson, Sidney Rice, Brandon Lloyd, Robert Meachem, Reggie Wayne and Marques Colston. They also never bit on trades involving RFAs Mike Wallace or Dwayne Bowe, which would have required them to part with a first-rounder and big money.

The Niners were linked to both receivers because of their apparent need at the position. There were a lot of folks that that a top-flight wide out would fast-track this team to a 6th Lombardi Trophy.

Bowe and Wallace are extremely interesting prospects, but not if you're fond of the players already on San Francisco's roster. If the 49ers were to make a play for one of these receivers, it would at least cost them Dashon Goldson.

They would also need to restructure the contracts of other players. It would not be wise with up-and-comers like Colin Kaepernick, Aldon Smith, Chris Culliver, Tarell Brown and Alex Boone all needing new deals in the not-too-distant future.

If the 49ers were to go against the team philosophy just this once, Greg Jennings stands out as the most likely signing.

Jennings is a veteran pass-catcher who has been in a winning environment for the duration of his career. At age 29, Jennings may not holdout for the six-year, $60 million contract.

San Francisco may be able to lure him to a winning environment on a reasonable four-year deal. He could comfortably play out the rest of his career, potentially win another Super Bowl ring and call it a career. Having played with Brett Favre, Aaron Rodgers and Colin Kaepernick would not be a bad way to go out as a WR.

While Jennings has been linked to Miami, Minnesota and Indianapolis, only one of those teams has a capable passer. Unless he is willing to drastically downgrade his QB for more money, Jennings may be convinced to come to the Bay Area.

Second-Tier

Devery Henderson and Danny Amendola

Since Harbaugh and Baalke have been pulling the strings, the 49ers have been methodical in their approach to FA. They simply do not agree with overspending on skill players, and much rather prefer to build through the draft.

It isn't a terrible approach because more often than not, the chances they do take in free agency are low risk - high reward moves. The 49ers have acquired second-tier FA receivers in Braylon Edwards, Mario Manningham and Randy Moss.

Edwards was the only complete miss out of the three of them. Manningham can return from injury and be very productive in this offense. While Moss was a very good addition for the year, providing invaluable knowledge to the younger players on the team.

But the 49ers can proceed with one of two things in mind:

1. "When it comes to wide receivers, we've been rolling the dice on unpopular names in free agency and in the draft, and two years later, it's still a need. Maybe we should ante up."

2. "Braylon's injury and Mario's injury were unpreventable and unforeseen. Randy was a great addition for the year - we got pretty close to a ‘best case scenario.' We should continue with our philosophy and it'll bounce our way"

It would be interesting to see the 49ers pursue Henderson or Amendola, although both will likely stay with their respective teams. However, with the offseason, you just never know.

The Rams recently claimed Titus Young off waivers and could look to the draft for another impact receiver if they can't fit Amendola under the cap. He showed that he can be quite injury prone and St. Louis is still rebuilding in the Jeff Fisher era.

However, Amendola is also incredibly productive when on the field. The other interesting aspect of this is that Danny Amendola and Michael Crabtree were teammates at Texas Tech. With Colin Kaepernick behind center, these two could be an explosive tandem once again.

And with Sean Payton returning to the Saints in 2013, New Orleans should retain Henderson. But if he were to field offers and see what was available, it could not hurt for San Francisco to get involved.

Henderson knows first-hand how good the Niners are. And unlike last year, San Francisco is now an attractive place for a wide receiver.

Third-Tier

Ramses Barden, Legedu Naanee, Brandon Gibson and Josh Cribbs

It still think there is value to be had by the lower level receivers that receivers. I don't doubt that the 49ers will be looking at these sort of options. I listed a few names above that I thought might be worth San Francisco's time.

I expect the Giants allow Barden to walk with Victor Cruz and Hakeem Nicks in need of contracts. Barden is 6'6", which makes him unlike any other receiver the 49ers have on the roster. The tallest wide out the Niners have is Crabtree at 6'1" and after that, everyone else is 6'0" or under.

Barden can still be considered as developmental, which is great for the 49ers. Also, the Giants have had a decent track record of bringing in wide receivers over the years.

Naanee and Gibson fit the same bill in that they can provide a threat down the field. They are not feature receivers but they can be role players in the offense. Gibson showed his skills in St. Louis this year, managing a pretty decent YPC with 13.5.

Though, at 6'2", Naanee is two inches taller than Gibson.

Naanee most notably spent time with the Chargers, playing with Phillip Rivers. He was never a big-time producer but he showed flashes here and there. Naanee, 29, still has pretty fresh legs and would be worth bringing into to compete at camp.

And finally, Josh Cribbs.

The 49ers will no doubt be parting ways with Ted Ginn Jr. who hardly played at all this season. He was not the full-time return man he was in 2011 and this time around, had a non-existent role on offense. Cribbs is looking to leave Cleveland, and anyone who has been in Cleveland for too long is probably eager for a winning opportunity.

Cribbs can find this in San Francisco.

He can have a prominent role on special teams and can contribute in the 49ers' deceptive but creative offense. It would not be a surprise at all to hear Trent Baalke was sniffing around Josh Cribbs.

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