Marcio Jose Sanchez/Associated Press

Khalil Mack's football career didn't merely adopt the darkness when he was drafted by the Oakland Raiders—it was born in it.

The outside linebacker/defensive end was left in the shadows as a recruit coming out of high school. ESPN didn't give him a grade, while Scout.com ranked him as only a 2-star prospect. Buffalo was the only school to offer Mack a scholarship, so he ultimately played there in the shadows of the top schools.

Despite playing at Buffalo, Mack was able to show off his skill set on a consistent basis. That skill set made him worthy of being a top-five pick in the 2014 draft.

Even though the NFL viewed him as a star, he was an after-thought behind the biggest stars of the class. Jadeveon Clowney was the most highly sought-after defensive player, while Greg Robinson and Sammy Watkins headlined the offensive side of the ball. Blake Bortles was a surprise selection ahead of Mack.

Although he was a top pick in the draft, he received little acclaim once his new team went off the clock.

That is because Mack went to the Oakland Raiders, a team that hasn't been in the national spotlight for a long time now. It's difficult enough for offensive players to receive the credit they deserve in Oakland, so a defender definitely wasn't going to get any credence.

Playing in front of the Black Hole in Oakland was fitting for a player who excelled during his rookie season without stealing any of the spotlight. Part of that negligence was Oakland's futility but also Mack's lack of individual production.

The outside linebacker played in all 16 games, compiling 76 tackles, four sacks and one forced fumble.

Undoubtedly, the Raiders hope that Mack can come away with many more sacks over the coming seasons, but the level of disruption he provided in 2014 was valuable. He was dominant against the run while consistently penetrating the pocket on passing plays, even if he didn't finish for sacks often enough.

Everything about Mack's play as a rookie suggests that he can become an All-Pro as soon as next season.

The 24-year-old carries significant bulk and is listed at 6'3" and 252 pounds. Yet, despite his size, he possesses an impressive burst and the fluidity to dip and bend around offensive linemen with ease. His speed allows him to shoot past either shoulder of an offensive tackle when he's left in space.

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On this play against the Kansas City Chiefs, Mack lined up as a right defensive end in a Wide 9 position. As soon as the center snapped the ball, he exploded off his right foot to attack the inside shoulder of the left tackle. The left tackle had initially dropped toward the sideline, so his momentum was pulling him away from Mack.

Even with the left tackle moving in the wrong direction, he should still have prevented Mack from penetrating past him so easily.

The tackle got his hands on Mack, but the rookie used his strength and balance to bend his body and dip beneath his attempt to push him off course. Once level with the line of scrimmage, Mack was able to accelerate toward Alex Smith in the pocket.

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Smith didn't hold onto the ball long. He hurried to get rid of it as soon as he saw Mack coming. The defender was still able to disrupt Smith's throw significantly, which led to an incompletion in the flat.

Considering his alignment to begin the play and the quick throw that Smith attempted, it was amazing that Mack got that close to the quarterback at all.

These were the types of plays that Mack made more than most edge defenders last year. Even though he wasn't getting sacks, he was still creating positive plays for his teammates by pressuring the quarterback to a point that he couldn't make comfortable throws.

Mack's ability to explode around the corner and dip beneath offensive tackles is going to make him one of the most potent pass-rushers in the NFL over the course of his career.

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A Week 3 display against the New England Patriots was arguably Mack's best of the season. He gave both offensive tackles problems in the game. Against Nate Solder on this play, Mack exploded past the sizable offensive lineman before fending him off with his low center of gravity.

Mack had beaten Solder from the beginning of the play, but a weaker defender would have allowed himself to be pushed past the play.

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Instead of pushing Mack past his quarterback, Solder fell down in desperation, while Mack hit Tom Brady in the pocket. Brady's pass went nowhere near its intended receiver as he absorbed the blow as he released the ball.

A split second of a difference cost Mack a sack and a forced fumble on this play.

The interesting aspect of his explosiveness during his rookie season is that it wasn't his greatest strength as a pass-rusher in college. Mack showed off a skill set that was closer to that of LaMarr Woodley, his teammate in 2014.

Woodley's skill set in 2014 wasn't like Mack's, but during his prime with the Pittsburgh Steelers earlier in his career, it was.

The heavy defensive end who converted to outside linebacker to fit into Dick LeBeau's defense had the explosiveness and flexibility to work in space, but he primarily relied on his bull rush to get to the quarterback. Big, strong arms with good hand usage allowed him to ragdoll opponents.

Mack didn't ragdoll many linemen during his first year in the league, but his power was a constant. It particularly stood out against the run.

Even as a rookie, it's hard to argue that he wasn't the best run-stuffing edge defender in the league last year. His ability to hold his ground against and beat double-teams was almost reminiscent of a nose tackle, while his awareness and power to force his way to the football were staples of his play.

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On this play from the same game against the New England Patriots, Mack lined up to the left side of the offense. He was in a linebacker stance and had only just settled in his spot as the ball was snapped. The Patriots were going to run directly at him.

Although he wasn't playing across from an offensive tackle, he was isolated against arguably the best blocking tight end in the NFL, Rob Gronkowski.

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Mack immediately engaged Gronkowski at the snap. Gronkowski is bigger than the outside linebacker, but Mack used his low center of gravity and hand placement to fend him off. Often, the tight end will maul smaller players from this position, but that isn't what happened with Mack.

Instead, Mack actually showed great control of Gronkowski as he pushed him back slightly with ease while looking inside for the football.

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Mack held the edge until he was certain that the running back, Stevan Ridley, was so far upfield that he wouldn't be able to cut outside without running into Mack. Once Ridley reached that point, Mack used his strength to toss Gronkowski aside and close on the running back.

Ridley made a sharp turn to try to run to the sideline, but Mack showed outside technique and athleticism to extend and drag him to the ground for a three-yard loss.

Stopping the run obviously doesn't attract attention the way racking up sacks does, but the value of what Mack does is huge. He's not just a good run defender; he's dominant to the point that teams should reconsider whether it's worth attacking his area of the field.

Of course, even when you run away from him, he has the athleticism to close on the play from behind to still be a factor.

Although Clowney's injury stole him of his rookie season, it's hard to think that anyone from the top 10 picks of last year's draft could have outperformed Mack as a rookie. Many of the opponents who were forced to deal with him in 2014 lauded his play afterward, according to Raiders.com.

Carson Palmer said, “No. 52 [Khalil Mack] is a phenomenal player. He’s a great pass-rusher, but he’s really good in the run game. We knew it was going to be a challenge.”

Brian Hoyer raved, “Talking to the guys in the locker room, he gained the respect of everybody on our team. That guy 52, Khalil Mack, is one of the best players we’ve gone against this year, and that’s a unanimous decision in that locker room. He gained all of our respect, and we knew coming in he was going to be a tough player."

Joe Staley had even more to say:

He’s super talented, a big physical guy and he plays hard. He’s everything you’re looking for in a hybrid ... defensive end. The stats might not show it, but he’s making a huge impact in the run game. He kind of reminds me of Clay Matthews the way he plays — smash-mouth. He’s a physical guy and he’ll try to overpower you with his strength. But he’s also developing counter moves as the season goes along, so he’s not just a one-trick guy. He’s a big challenge.

Staley touched on the most important part of Mack's development moving forward. If he develops a wide range of effective pass-rush moves, there will be no stopping him because of his athleticism.

Even if he doesn't develop those moves, he should still be a productive pass-rusher with what he was doing by the end of his rookie season. It's rare that pass-rushers come into the NFL and immediately dominate.

Many of the best pass rushers in the NFL had muted production as rookies.

Player Rookie Year Second Year Third Year Fourth Year Robert Quinn 5.0 10.5 19.0 10.5 J.J. Watt 5.5 20.5 10.5 20.5 Justin Houston 5.5 10.0 11.0 22.0 Mario Williams 4.5 14.0 12.0 9.0 NFL.com

None of the four pass-rushers above had more than six sacks during their rookie seasons. It was simply a reflection of where they stood in their development process. While Mack also didn't cross six sacks, he drew the second-most holding penalties of any defender in the NFL last year, according to Football Outsiders.

Mack drew eight penalties, just one less than the league leader, Jason Pierre-Paul.

It appears inevitable that the Raiders will eventually have a player worthy of being considered alongside Von Miller, Justin Houston and Robert Quinn as one of the best edge defenders in the NFL. Unearthing a player with such a well-rounded and elevated talent level is difficult to do.

Matching it with the consistency and intensity that Mack showed off during his rookie season is even tougher.

Based on what he did during his rookie year, there's no reason to think he won't elevate himself to that level sooner rather than later. Mack should be capable of making an All-Pro team next year, even though his chances will be hurt if the Raiders are an uncompetitive team.