The Raiders have high expectations for the duo of Amari Cooper and Derek Carr, and Reggie McKenzie's spotty free agency track record seems to be the Oakland rebuild's last hurdle to clear.

The most proven way, albeit the most frustrating and time-consuming, for a downtrodden NFL franchise to turn competitive again is by excelling in the draft. Luring a big-name free agent is a nice boost for the fan base, but rarely does a team find success without getting the job done in April or May.

The Raiders may finally have figured that out.

Oakland did not have a first-round pick in 2011 as a result of trading for Richard Seymour and did not pick in rounds 1 or 2 the following year after chasing Carson Palmer. The Raiders did manage to post back-to-back 8–8 marks with Seymour and later Palmer on the roster—their best records since going 11–5 and winning the AFC back in '02—but the acquisitions did little to help in the long run.

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The spoils of the most recent three drafts could. A boatload of players from the 2013 and '14 drafts are projected as starters this coming season, and that group will now be joined by No. 4 pick Amari Cooper and possibly third-rounder Clive Walford. Perhaps no team has accomplished as much in recent draft history.

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Where this turnaround gets a little tricky is in general manager Reggie McKenzie's latest attempt to supplement his strong draft work by flipping over a huge chunk of the roster with free agents. Oakland signed no fewer than a dozen players, some ticketed for critical roles: center Rodney Hudson, linebacker Curtis Lofton, defensive tackle Dan Williams, safety Nate Allen, running back Roy Helu and maybe even wide receiver Michael Crabtree. Others (/waves to Christian Ponder) will see the field only in an emergency.

Unfortunately for the Raiders, McKenzie failed to convince any big-ticket free agents to don the silver and black, despite opening the off-season with approximately the GDP of Iceland free under the salary cap.

Still, McKenzie did stay active. Oakland chose to let former center Stefan Wisniewski walk. Same with free-agent bust LaMarr Woodley, safety Tyvon Branch and running back Darren McFadden. Their replacements should have no trouble exceeding that trio's production.

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This roster is set up to be as competitive as it has been since the Seymour-Palmer years. Better yet, the foundation has been laid for Oakland to soon complete its rebuilding project.

Grade: A–

Best acquisition: Amari Cooper, WR

Those inside the Raiders' offices may be higher on quarterback Derek Carr after one year than those outside. But for Carr to take any realistic shot at taking the next step, he needed more help around him.

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Enter Cooper, the draft's top wide receiver—a polished, reliable pass catcher outside who immediately should become the No. 1 option in the passing attack.

“It’s very nice when it goes hand in hand," McKenzie said in a press conference after selecting Cooper. "You get a chance to get a great player and he fits one of the needs, so it’s great when that falls in place."

Cooper caught an NCAA-best 124 passes last season, for 1,727 yards and 16 touchdowns. Between those numbers and his spot on Oakland's depth chart, the expectations for him may hover around Odell Beckham Jr. territory: 80-plus catches, 1,200-plus yards and double-digit touchdowns. That is an extremely high bar to set for a rookie, especially one with a second-year quarterback throwing him the ball.

“The expectation level should be high for a young man that comes in that is selected that high in the draft," new Oakland head coach Jack Del Rio said. “But he’ll need to prove it on the field and earn it. That’s how, really, it is with everybody."

Even if Cooper cannot match Beckham's output, leading the Raiders in receiving will be well within reach. Andre Holmes held the honor last season at a mere 693 yards; James Jones's 73 catches (with a miserable 9.1 yards-per-catch average) led the team.

The Raiders are counting on Cooper to be a game-changer for their offense. While it may be prudent to reel in the forecast some, the Alabama product has the talent to be a great NFL player.

Biggest loss: Tarell Brown, CB ...

... but that's only because someone had to get the nod. In reality, Oakland will not feel the sting from any of their losses if things go according to plan. Hudson appears to be a (pricey) upgrade on Wisniewski; rookie Mario Edwards Jr. has far more upside than Woodley, though the coaching staff has to figure out some way to tap into it; Allen slots in for Branch, who missed most of 2014 with a foot injury; and Helu offers a more well-rounded game than McFadden.

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As for what the losses of Brown and Carlos Rogers mean, it all depends on how ready the young secondary base is to handle more responsibility. Brown did turn in a decent 2014, playing 1,000 snaps. The Raiders, though, believe they have enough starter material in '13 first-rounder D.J. Hayden and second-year cornerbacks Travis Carrie and Keith McGill to keep moving forward.

Keep an eye on former undrafted free agent Neiko Thorpe, too. He provides yet another young, rather unproven option.

“I feel like we have some solid young players that should develop in our system, and so throughout the whole roster we’re looking for ways that we can create competition and make sure that we develop," Del Rio said at this year's scouting combine. “I see that position much like the rest of the positions on the team: I think it’s one that had some moments, one that will need to play at a better level and I think you can say that throughout the roster."

Underrated draft pick: Ben Heeney, LB, Kansas (round 5, pick No. 140)

Third-round tight end Clive Walford likely will have more impact on the 2015 season. He's a versatile playmaker and should pair well with incumbent Mychal Rivera.

However, if we're really seeking out a diamond in the rough, look no further than Heeney. The 6-foot, 231-pound defender is exactly the type of player coaches love to have on their rosters—an aggressive, high-effort linebacker with a definite future at least as a special teams weapon.

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​Heeney does not hit a lot of the measurable marks scouts desire at linebacker, standing a bit undersized and lacking much of a second gear. He was a first-team All-Big 12 defender last season nonetheless.

Lofton is penciled in as the Raiders' third starting linebacker, next to Sio Moore and soon-to-be superstar Khalil Mack. Heeney's a nice depth piece behind that grouping, and he could develop into a starter down the line. His tendency to pin his ears back in pursuit of the football, occasionally at the expense of his assignment lane, would be less of a hindrance with Mack and Moore covering for him.

Looming question for training camp: Who's carrying the rock?

A lot of guys, probably. The best of the bunch last year, in surprising fashion, was Latavius Murray. He averaged 5.2 yards on 82 attempts, highlighted by a 90-yard touchdown run during Oakland's upset win over Kansas City. Compared to McFadden (534 yards on 155 carries) and Maurice Jones-Drew (96 yards on 43 carries), Murray looked like 1989 Bo Jackson.

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​Helu is a meaningful reinforcement for 2015. In limited action last season with Washington, Helu gained 693 yards from scrimmage—477 of them coming on 42 receptions. Carr will appreciate having such a viable safety valve on passing downs, plus Helu has shown flashes of being ready for more as a true running back.

The same cannot be said of fellow new arrival Trent Richardson, who will go down as one of the most disappointing Indianapolis Colts of all time. Oakland would like him to provide relief for Murray and Helu between the tackles, but don't count on it.

A preferable solution would be for the new Oakland regime to get fullback Marcel Reece more involved. He saw all of 21 carries last season, although Reece did make 37 receptions. That's still not enough touches for a talented player.