Minnesota Vikings' 2018 free agency: Sheldon Richardson plugs hole at DT

Savage, Siemian on the move (0:34)

Adam Schefter reports that the Broncos are finalizing a deal to send Trevor Siemian to Minnesota while Tom Savage has reached an agreement with the Saints. (0:34)

A breakdown of the Minnesota Vikings' 2018 free-agent signings:

Sheldon Richardson, DT

The Vikings have signed Richardson, who played the past year for the Seattle Seahawks after four seasons with the New York Jets. Here's a closer look at the signing:

Grade: A. The Vikings scored another high-profile free-agency win a day after inking quarterback Kirk Cousins to a fully guaranteed contract. Minnesota signed two Pro Bowlers in as many days and gave its top-ranked defense a major boost on the interior of the line.

What it means: The 3-technique spot was arguably the second-biggest priority for the Vikings this week. Landing Richardson puts the Vikings in the debate for the best defensive lines in the NFL, with Philadelphia and Jacksonville. This season's starting four could feature Danielle Hunter, Linval Joseph, Richardson and Everson Griffen. Try to imagine that pass-rush combination for a minute.

When the new league year rolled around on Wednesday and Tom Johnson and Shamar Stephen became free agents, Minnesota had only 58 snaps from the second defensive tackle spot on its roster. Plugging Richardson next to the Joseph, best nose tackle in the league, will not only boost the run defense immediately but also provide a more stable rotation with the pass rush in areas like third down. Richardson had only one sack in 2017 but generated pressure with 28 hurries and seven quarterback hits, according to Pro Football Focus. Time will tell, but this may be the best defensive line in Minnesota since Jared Allen, Kevin Williams, Pat Williams and Ray Edwards in the 2000s.

The Vikings worked tirelessly Thursday after signing Cousins to get this deal done. In order to do so, Minnesota had to restructure Latavius Murray's contract before $5.15 million of his 2018 salary became guaranteed on Friday. So out of the Richardson deal, the Vikings were also able to maintain the Dalvin Cook-Murray backfield.

What's the risk: Neither of the Richardson's last two teams have wanted to commit to him for the long haul. The Jets tried to move the former first-round pick before the trade deadline in November 2016 and sent him to Seattle ahead of last season. The Seahawks reportedly wanted to retain Richardson after his first season there, but they let him walk in free agency. Richardson was arrested twice, in 2015 and again in 2016, with the Jets. The biggest risk the Vikings take here deals with off-field concerns, not Richardson's ability to provide an interior pass-rushing presence.

Trevor Siemian, QB

The Vikings are finalizing a deal to acquire Siemian, who played the past three years for the Denver Broncos. Here's a closer look at the signing:

Grade: B-minus. Yes, Siemian struggled in the Denver quarterback carousel last season and played behind a porous offensive line, and his numbers under pressure were the worst among all qualifying QBs. However, the cost to bring the 26-year-old to Minnesota via a trade (he has a $2 million cap hit) wasn't steep, and the chance for him to work with QB guru John DeFilippo could turn Siemian into one of the better backups in the league.

What it means: The Vikings really like former Broncos quarterbacks. Siemian joins the backup mix with Kyle Sloter, the second-year reserve the Vikings fought to land as a practice-squad QB after he was waived by Denver before the 2017 season started. With starter Kirk Cousins expected to ink his deal Thursday, the quarterback room is set in Minnesota. Siemian brings experience, having started 24 games over the past two seasons, throwing 30 touchdowns to 24 interceptions with a 59.3 career completion percentage. He can manage an offense and move the ball downfield with the right protection and personnel at his disposal. He'll have plenty of that in Minnesota.

What's the risk: Siemian underwent surgery two months ago after suffering a dislocation of his left (non-throwing) shoulder in Week 14, the same shoulder that was surgically repaired 12 months prior. Outside of his recent injuries, getting Siemian into a backup role is as solid a move as the Vikings could make, particularly for the price.

Kirk Cousins, QB

The Vikings will sign Cousins, who played the past six years for the Washington Redskins. Here's a closer look:

Grade: A. Regardless of where you think Cousins ranks in the NFL quarterback hierarchy, the Vikings went after and landed exactly who they wanted. Minnesota held off the Jets, who could have offered more money, the Broncos and the Cardinals. The Vikings took a gamble going into free agency by not tagging Case Keenum (with the intent to trade him) or holding on to Sam Bradford or Teddy Bridgewater as insurance, instead hedging all of their bets on landing Cousins and hoping he can solve their issues of instability at the position. Chalk this up as a major win for a franchise vying to get back to the NFC title game this season and take another step toward Super Bowl LIII.

What it means: Cousins is the missing link for the Vikings at arguably the most important position in all of sports. In the past three seasons, he ranks top 10 among all players in completion percentage, yards per attempt, passing touchdowns and Total QBR. He also provides Minnesota with the stability at quarterback it hasn't had in a decade as one of six quarterbacks to start every game since 2015. The Vikings' offense will take a massive step forward by installing Cousins and pairing the passer with noted quarterback guru and innovative offensive mind John DeFilippo. Give Cousins Adam Thielen and Stefon Diggs plus an explosive backfield with Dalvin Cook and the No. 1 defense in the NFL and the Vikings are heavyweights in the NFC.

What's the risk: Despite the consistency of his past three seasons, when he threw for more than 4,000 yards each year, Cousins' struggles have been magnified with turnovers in the red zone, fumbles, diminished clutch throws under pressure and a middle-of-the-pack adjusted completion percentage in 2017. Not all of that was his fault (he performed better when he had DeSean Jackson versus when he didn't), but naysayers will point to the notion that no one truly knows how much better Cousins is than Keenum. In the right system, which the Vikings believe is theirs, Cousins has the potential to become a franchise quarterback and take the next step in his career. The price for Cousins -- an expected three-year fully guaranteed deal worth $84 million -- might haunt the Vikings if they're unable to agree to extensions (Anthony Barr, Eric Kendricks, Diggs and Danielle Hunter all come due in 2019, plus Trae Waynes' fifth-year option) or sign future free agents because of limited cap space. A deal like this changes the market to where Cousins might want something similar if he hits free agency again at 32. Right now, however, that's not a chief concern. The Vikings got their guy and have all the pieces available to help him take his game to the next level.

Nick Easton, OG

The Vikings are expected to place a second-round tender on guard Nick Easton. He played the past two years for the Vikings after going undrafted out of Harvard in 2016. Here's a closer look at the signing:

Grade: B Interior offensive line depth is a priority for the Vikings. Though there might be some continued shuffling at the guard spots depending on whether Joe Berger returns and if Mike Remmers does or doesn't move back to right tackle, offering a second-round tender before Easton becomes a restricted free agent on Wednesday takes Minnesota one step further in figuring out who will protect Mystery Quarterback X in 2018.

What it means: Easton struggled at times to run block in 2017 but was one of the better pass-blocking linemen among the starting five. His versatility on the interior is crucial, especially with his experience of playing guard and center. His tender is worth $2.914 million, and if Easton departs for a different team in free agency, the Vikings would get a second-round pick in return.

What's the risk: Easton told ESPN in January that he expects to be ready to participate in the Vikings offseason program this spring. The left guard suffered his first season-ending injury when he broke his left ankle in Green Bay and was sidelined with a calf injury for several games after getting hurt Week 5. Easton was a solid fit as a starter in a unit that was forced to shuffle pieces around after a wave of injuries occurred in the middle of the season. Both Easton and center Pat Elflein underwent surgery to repair fractured ankles, but are on pace to be full-go by the start of the season.

Anthony Harris, S

Vikings fourth-year safety Anthony Harris signed his exclusive rights free-agent tender worth $705,000 on Monday. Here's a closer look at the signing.

Grade: B Harris played a key role last year, appearing in 16 games and taking over starting duties when Andrew Sendejo was forced to miss three games due to injury and suspension. He's a reliable fit in the secondary and plays a critical role on special teams.

What it means: Harris returns for his fourth season with the Vikings now that his tender is in place and is locked into Minnesota on a one-year deal. The safety has appeared in every game in the last two seasons and made six starts, notching 18 tackles and a forced fumble in the regular season and 11 additional tackles in two playoff games. While the question marks are so much greater on offense, the back-end of Minnesota's top-ranked defense stays intact with the signing of Harris' RFA.

What's the risk: Very little involved with Harris. When Sendejo was forced to miss games, Harris was able to step in seamlessly and fill the void. He battled through knee and hamstring issues at points last season, but nothing was serious enough to keep him sidelined.