Every NFL rookie carries with him a certain set of expectations, whether he was drafted to be a franchise savior or latched on with a team as a free-agent flier. Some first-year pros leave those expectations in the dust while others struggle mightily to meet them.
Evaluating prospects is, to be sure, an inexact science. It is tough to know what a guy truly is made of until he gets into the thick of real, live NFL action. Now that we're five weeks into the 2013 season, I thought I'd look at who in this rookie class has outplayed expectations entering the league -- and who has fallen far short.
Those who largely have played up to their draft positions were not included in this piece. That's why you won't find guys like Barkevious Mingo and Ziggy Ansah below; yes, they've excelled, but that's what they were expected to do as lofty draft picks. Similarly, while Eric Fisher, Lane Johnson and Luke Joeckel (whose season was ended prematurely by an ankle injury last Sunday) haven't exactly set the world on fire, I still think they'd be drafted where they were originally. You also won't find players who don't have a body of work that can be judged yet, like third overall selection Dion Jordan.
Finally, keep in mind that this is not an exhaustive list; 254 players were drafted last April, and many more were signed as rookie free agents. It would be impossible to cover them all. I merely wanted to highlight a handful of rookies who have surpassed expectations and a handful who have not. Here they are, presented in alphabetical order:
FIVE THRIVING ROOKIES
Kiko Alonso, LB, Buffalo Bills
Drafted just 46th overall, Alonso has been a big surprise, looking like a bona fide Defensive Rookie of the Year candidate while racking up 44 tackles, four interceptions, four passes defensed, one sack and one forced fumble in five games as a pro. A starter from Week 1, the competitive linebacker plays with a chip on his shoulder, never slowing down. He also plays better than expected when in space. September's Defensive Rookie of the Month has definitely outplayed his original draft slot.
Marcus Cooper, CB, Kansas City Chiefs
As the season goes on, teams are going to be asking their scouts about this promising young corner. Cooper has five passes defensed, one interception and one forced fumble in five games and one start -- which, by the way, is as many starts as he had at cornerback in college at Rutgers. The smart, strong Cooper has the kind of cover skills that are rarely seen in a rookie. He looks like former standout cornerback Al Harris, who wore the same number (31) as Cooper -- and happens to be his position coach with the Chiefs. Kansas City general manager John Dorsey and his staff earned their paycheck digging out this gem, who was released by the San Francisco 49ers after being drafted in the seventh round.
John Jenkins, NT, New Orleans Saints
Jenkins has had a big hand in the Saints' defensive improvement this season, collecting 10 tackles in five games (four starts). The impossible-to-move run-stuffer has very good feet and outstanding short-area quickness. While he is not a pass rusher, he can collapse the pocket and is a great fit for the defense that New Orleans runs. Picked 82nd overall last April, he'd be a first-round choice based on what he's shown thus far this season.
Kyle Long, G, Chicago Bears
Chicago was criticized for picking the relatively inexperienced Long 20th overall, but through five starts, he's outplayed even that high slot. Long has a defensive lineman's temperament and a receiver's athletic ability. He can pull and get to the second level, and he does a very good job in pass protection. It's amazing to see a player as green as Long playing this well; he'll be a force for the Bears for years to come.
Tyrann Mathieu, S, Arizona Cardinals
Mathieu has unbelievable ball skills and playmaking ability. He plays bigger than his height (5-8 3/4) and faster than his timed speed (4.51-second 40-yard dash). He can do everything, including tackling: he has 34 stops in five games, second-most on the team. Mathieu is confident, aggressive and alert; if the opposition fumbles, there's a good chance he'll be the one to fall on the ball. Though he doesn't excel in man coverage, he has great reactions when playing zone. Mathieu has all the makings of a star at safety. Drafted in the third round last April, he could go at least one round earlier if picked today.
Others deserving mention: David Bakhtiari, OT, Green Bay Packers; DeAndre Hopkins, WR, Houston Texans; Cordarrelle Patterson, WR, Minnesota Vikings; Geno Smith, QB, New York Jets; Kenbrell Thompkins, WR, New England Patriots; Kenny Vaccaro, S, New Orleans Saints.
FIVE FALLING SHORT
David Amerson, CB, Washington Redskins
Amerson is a former pro-day standout who has not played up to his speed. He struggles in man coverage, gambles and is undisciplined (double moves hurt him). His size and speed -- plus the 13 interceptions he collected in 2011 for N.C. State -- probably pushed him into the second round of the draft, but he seems to lack the skills needed for coverage. After all, he's made just two starts this season for a Redskins defense that can't stop anybody; struggling to stick in a lineup like that is a troubling sign.
Tavon Austin, WR, St. Louis Rams
Austin showed rare ability to create at the college level. I thought this would translate into big plays in the pros, but the West Virginia product has failed to make much of a mark, totaling just 23 catches for 156 yards and two touchdowns in five games. I think the tackling skills and speed of NFL linebackers make it difficult for a guy like Austin to break away in the open field, and he doesn't seem to get separation on his routes. I still like this player, but he has not matched the excitement that accompanied his entry to the league. His struggles encapsulate the difficulty of transitioning from college to the NFL, especially at his size (5-foot-8 1/2, 174 pounds). I think the eighth overall pick actually would go somewhere in the second round today.
DJ Hayden, CB, Oakland Raiders
Hayden, who has one interception and two passes defensed in five games, is a backup corner whose arms aren't very long. It doesn't look like he's playing with the aggressiveness he had before suffering a life-threatening injury in college. I don't think Oakland needed to draft him 12th overall; I believe the Raiders could have traded down, snagged an extra pick and nabbed Hayden at the end of the first round.
Datone Jones, DE, Green Bay Packers
The 26th overall pick has only one tackle in four games (no starts), failing to register in any other statistical category. Jones plays hot and cold; he's a tweener who is not big enough to play tackle and not explosive enough to play defensive end. When I evaluated him out of college, he seemed like a boom-or-bust type who didn't appear to have any one standout trait.
Dee Milliner, CB, New York Jets
Drafted with the ninth overall pick shortly after the Jets' high-profile trade of elite cornerback Darrelle Revis, Milliner has not made much of an impact as a rookie thus far, collecting just four tackles in three games (two starts). Milliner didn't seem to have great coverage skills at the NFL Scouting Combine, and he hasn't assuaged my concerns since. He also needs to be more physical as a tackler; he has a tendency to leave his feet. I know Milliner has been dealing with injury issues, but I still don't think he has the ball skills needed to be a top cornerback. If drafted again, he'd go late in the first round or early in the second.
Follow Gil Brandt on Twitter @Gil_Brandt.