Vikings free agency tracker: What's happened and what needs to happen

Vikings free-agency tracker …

We're tracking all things Purple, starting with what's already happened and projecting what still needs to happen as the Vikings work their way through free agency. Here we go:

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QB Matt Cassel: Agreed to terms on a two-year, $10 million deal on March 8. Signed the deal March 10.

What it means: The Vikings would have gone into free agency with their No. 1 need being a veteran quarterback to serve as their temporary bridge to the future. Cassel, who went 3-3 and played in all five of the Vikings' wins a year ago, isn't perfect, but he's the best-case scenario in a weak quarterback market. Now, the Vikings can shift their QB focus to picking the right one in the draft.

DE Everson Griffen: Agreed to terms on a five-year, $42.5 million deal on March 8. Signed on March 10.

What it means: A starting right defensive end to replace Jared Allen would have been priority No. 2 heading into free agency. Signing the 26-year-old Griffen filled that need with a familiar player who's been solid, is full of star potential and is heading into his prime seasons.

What it means: The Vikings let Brinkley, a starter in 2012, walk away before the 2013 season. Then he failed in Arizona and was released after the season. So we're not talking any guarantees here. He will compete with Audie Cole and Michael Mauti at middle linebacker with perhaps one of them being able to move over and compete with Gerald Hodges at the weak-side linebacker spot.

C-G Joe Berger: Signed a one-year deal March 11.

What it means: Berger might be the most underrated player on the team. He's primarily a center, and he's been good enough to start there. But he also can be a serviceable starter and backup at both guard positions as well.

RB Matt Asiata: Exclusive rights free agent signed his one-year tender.

What it means: Asiata is a good No. 3 running back and special teams player. The Vikings still can use a change-of-pace back with pass-catching skills as their No. 2 back.

What it means: Evan will continue to provide depth on the nose, which is something he's done with the Vikings since 2007. He's not a front-line talent, but is a wide body with experience. Makes too many silly encroachment penalties while lined up with his head right over the ball, but is a good player to have for depth and emergency situations.

WR Jerome Simpson: The acrobatic, but inconsistent veteran receiver signed a third consecutive one-year, "prove-it" deal with the Vikings on March 14.

What it means: Focusing just on football, it means the Vikings now have four experienced receivers to go along with tight end Kyle Rudolph. Are those four receivers written down in pen as the top four that will start the season? No. Beyond Cordarrelle Patterson and Greg Jennings, anything can happen, depending on whether the Vikings come across something better between now and September. But Simpson gives new offensive coordinator Norv Turner a deep threat that can leap and pick passes out of the air. Of course, Simpson also is prone to disappearing for long stretches, dropping too many passes and getting in trouble off the field. His arrest for DWI last December could result in another league suspension to go with the three-game punishment he served when he joined the Vikings in 2012.

LG Charlie Johnson: Agreed to a two-year, $5 million deal on March 15.

What it means: Although he struggled last season and the Vikings were willing to lose him while they focused on higher priorities, Johnson has started 48 of 49 games since joining the Vikings in 2011, including all but one game at left guard the past two seasons. With Johnson's return, the starting line should remain intact for a third straight season. General Manager Rick Spielman said he's impressed by the progress of Jeff Baca, a sixth-round pick a year ago, and that the team will be looking to address the offensive line in the draft. But re-signing Johnson, 30, for about $2.5 million this season suggests the Vikings are willing to let Johnson handle the position while they groom a backup that could take his spot as early as 2015.

NT Linval Joseph: Agreed to a five-year, $31.5 million deal on March 11, the first day of the signing period.

What it means: Well, the Vikings didn't have a starting-caliber nose tackle on the roster. They also haven't had a true nose tackle in top form since Pat Williams' last dominant season in 2009. Not coincidently, that was the last time the Vikings played shut-down run defense. Priority No. 1 defensively for new coach Mike Zimmer is shut-down run defense. Joseph is a 6-4, 328-pounder who's only 25 and was a second-round pick in 2010.

CB Captain Munnerlyn: A competitive, hard-nosed, 5-8, 195-pounder, he signed a three-year, $14.3 million deal with $7 million guaranteed on March 13.

What it means: The Vikings finally have someone to replace Antoine Winfield, 12 months after making a calculated, financial-based mistake in releasing him and placing blind faith into Josh Robinson, a second-year pro who had never played inside over the slot in the nickel defense. Munnerlyn has three years of experience at starting outside and sliding inside when his former team, the Panthers, went to the nickel. He's also a 25-year-old rising star who made plays on a defense that ranked No. 2 in the league in yards and points allowed last season. In five seasons in Carolina, Munnerlyn, a seventh-round draft pick in 2009, returned five of seven career interceptions for touchdowns. The guy he replaces, Chris Cook, a second-round pick in 2010, is still looking for his first career pick. He signed with the 49ers on March 14.

CB Derek Cox: The 6-1, 180-pound Cox signed a one-year deal on March 13 and hopes he can reclaim what he had for four years in Jacksonville and lost last season in his only year with the Chargers.

DT Tom Johnson: At 6-3 and 290, the 29-year old signed a one-year contract worth $875,000 on March 20.

What it means: He's another cog in the middle of the defensive line. Settled in with the Saints the past three seasons after moving all over the world to play, but New Orlean's 3-4 didn't suit him. Will likely be at three-technique, although his experience at end could make him versatile. A bit old, but it's a low risk and Zimmer clearly wants to improve the interior line.

DL Corey Wootton: The 6-6, 270-pounder got a one-year deal worth $1.5 million, plus incentives, on March 21.

What it means: Wootton can play both tackle and end, but is likely to be more of the latter under Zimmer. He had a hip issue that hampered him in Chicago, where he played the past four years. Wootton started 15 games for the Bears last season, so he's not chopped liver. This is an intriguing signing, if he returns to full health.

OG Vlad Ducasse: The 6-5, 320 pound Ducasse visited Winter Park early in free agency, and agreed to a one-year deal Sunday.

1. Veteran quarterback (Re-signed Matt Cassel)

2. Starting right defensive end (Re-signed Everson Griffen)

3. Young, true run-stuffing nose tackle (Signed Linval Joseph)

4. Cornerback (Signed Captain Munnerlyn and Derek Cox)

5. Left guard (Re-signed Charlie Johnson and added Vlad Ducasse)