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Ndamukong Suh, DeMarco Murray and Randall Cobb were among the big fish the Oakland Raiders tried and failed to land in free agency. Even a truckload of cash as bait couldn’t change the fact that general manager Reggie McKenzie was still fishing with a twig and dental floss.

Quietly, McKenzie did reel in a stream of upgrades early in free agency, which cumulatively may be enough meat to feed a roster hungry for talent. It’s about the best he could do in an environment that scares away the few free agents worth dipping into long-term reserves to catch.

Unlike last year, McKenzie signed players who are still in their primes. The Raiders do still have several free agents they brought in last year, so the younger age of the players signed this year coupled with a new coaching staff could be just the thing to get the Raiders back on track.

Maybe it’s a good thing the Raiders didn’t throw fat stacks of cash at only a few players and instead took the approach that more than twice as many upgrades will make a bigger overall impact. Free agency isn’t the right place to build a team, and many of the big free agents of today are the cap casualties of tomorrow.

By spreading out the money, the Raiders are also spreading out the risk. Whiffing on a high-profile free agents can be costly both on and off the field, but players can also get hurt. The exorbitant guarantees required to bring in certain free agents can wreak havoc on the salary cap, but a couple misses on second-tier free agents should leave the team in good shape as long as they also draft well.

The Raiders have also structured contracts wisely, which makes it easier for them to move on from mistakes after a season or two if necessary. No general manager hits on every move, so team-friendly contract structures ensure the team doesn’t go through a period of salary-cap issues when a few of them don’t work out.

McKenzie is no stranger to contract and player albatrosses as the Raiders just emerged from a salary-cap hangover last year. Six teams have more than $15 million in dead money so far in 2015, which in almost every case is due to multiple big free-agent contracts not working out.

Three players signed by the Miami Dolphins two years ago who are no longer on the roster count $15 million against their salary cap in 2015. The New Orleans Saints have three players counting $20 million against their salary cap, including linebacker Curtis Lofton, one of the many free agents the Raiders recently signed.

Of course, smart salary-cap management only matters if the Raiders improve on the field. All it will do is make it easier for the next general manager to put his stamp on the team if they don’t improve in 2015.

We won’t know if the Raiders truly got their money’s worth until the season, but we do have a good idea what they are getting in each player. The players the Raiders signed shouldn’t begin to decline for another couple of years, which means they should be capable of repeating their performances over the last couple of years.

Cumulative PFF Snaps and Grades 2013-2014 Addition Snaps 2013-2014 PFF Grade 2013-2014 PFF Grade 2013-2014 Snaps 2013-2014 Replacing Rodney Hudson 2148 20.6 8.9 1971 Stefen Wisniewski Dan Williams 766 19.7 4.7 1122 Pat Sims Nate Allen 2321 1.6 -30.8 1718 Brandian Ross Curtis Lofton 2128 -21.5 -49.9 2201 Miles Burris & Nick Roach Lee Smith 779 9.1 -2.1 778 Brian Leonhardt & Jeron Mastrud Malcolm Smith 919 3.1 -5.5 361 Ray Ray Armstrong & Kaluka Maiava Roy Helu 929 -0.3 -19.4 880 Darren McFadden James Dockery 105 -4.6 -9.6 258 Chimdi Chekwa Christian Ponder 611 -13.4 -8 408 Matt Schaub/Matt McGloin Difference 10706 14.3 -111.7 9697 Difference Pro Football Focus

At least according to Pro Football Focus grades, the Raiders improved significantly in free agency. Nearly every signing with the possible exception of backup quarterback was also an upgrade (see chart). The players that the Raiders signed this offseason have a cumulative grade of 14.3 over the last two seasons, while the players they will replace have a cumulative grade of negative-111.7.

In total, it’s a difference of 126.0 grading points, or roughly 18 points on offense and 45 on defense per season. If we were to adjust the Raiders’ grades last season, the closest comparable team would be the St. Louis Rams, who were much better than their 6-10 record.

It’s an interesting way to visualize just how much the Raiders potentially improved in free agency. Other variables will affect how things come together in 2015, but McKenzie has made an impact in free agency. Head coach Jack Del Rio and his staff certainly have a lot more talent to work with than they did just two weeks ago.

The Raiders’ plan has crystalized, and it’s now clear that this was their plan the whole time. They obviously chased after Suh, Cobb and Murray for a reason, but missing on them didn’t change much. Other than defensive tackle Dan Williams, Oakland’s other signings would have been unaffected by those signings.

McKenzie surprisingly let center Stefen Wisniewski hit free agency and then signed the only upgrade available in Rodney Hudson. The Raiders cut safety Tyvon Branch and then signed Nate Allen as his replacement, which will actually allow Charles Woodson to play in the box more often where he is best.

The Raiders even quickly moved to sign Lofton after the Saints released him because he was one of the only inside linebackers on the market that was a starter last season. He’ll replace Miles Burris, who was one of Oakland’s worst starters at any position in 2014. Malcolm Smith will also help at linebacker and knows defensive coordinator Ken Norton Jr. well as he was his position coach in Seattle.

Running back Roy Helu is an underrated player who is a perfect fit in new offensive coordinator Bill Musgrave’s scheme. Helu will help second-year quarterback Derek Carr as a safety net in the passing game and solid option as a reserve runner if needed.

Then there’s blocking tight end Lee Smith, who should be a huge upgrade over the rotation the Raiders have had at that position since Zach Miller left in free agency several years ago. The combination of Hudson, Helu and Smith isn’t flashy, but they should take a lot of the pressure off Carr in 2015.

Williams signed to anchor the run defense and try to build on some of the success he had as a pass-rusher last season. Even if he proves only to be a great two-down player, the Raiders have defensive tackle Antonio Smith and defensive end Justin Tuck who can play inside on passing downs.

Inside of trying to find that one free agent who will make everyone forget about all the holes on the roster, the Raiders are doing their best to fill those holes with quality young players. If you consider the injury rate in the NFL, it’s not a bad plan. A big investment can become a sunk cost the instant a star player blows an ACL.

The Raiders have more work to do because they still have several holes headed into the draft. Pass-rusher, wide receiver, right guard and running back are high atop the list of needs. Possible free-agent additions include defensive end Anthony Spencer, wide receiver Greg Jennings, guard Justin Blalock, guard Mike Pollak and running back Chris Johnson. They are all just on the wrong side of the age curve at their positions.

Younger options include Michael Crabtree at wide receiver, Greg Hardy at defensive end (who the team isn’t pursuing) and Trent Richardson at running back. All of those players come with different levels and types of baggage, which the Raiders may not be inclined to invite into a stable locker room at this point.

Even if the rest of the signings this offseason are for depth and they still have holes headed into the draft, the Raiders got better in free agency without mortgaging the future. The draft is the deepest at wide receiver, running back and edge-player, so the Raiders should be able to find their solutions there without having to reach.

After an initial panic about what the Raiders were doing (or not doing), they’ve quietly signed a group of players who can make positive impact in 2015. That alone should excite the Raiders fans, who haven’t had much to cheer about in over a decade.

Unless otherwise noted, all statistics via Pro Football Focus (subscription required) and all cap information via Over The Cap.