For those invited and participating in the 2015 NFL Combine, what matters? What’s the most important thing to watch out for? They’re all talented and they all have elite skills, but there are keys that every scout and GM will be looking at. Here’s what each prospect has to prove … 

1.Denzel Perryman, Miami 6-0, 242
Some scouts are going to demand that he’s the No. 1 inside linebacker on the board if he’s able to come up with a great workout. He’s a fantastic leader, he’s built like a true middle linebacker, and he’ll tackle everything, but is he quick compared to the rest of the top options in this class? You know what you’re getting, but he has to show that there’s the potential for more. 

3.Eric Kendricks, UCLA 6-0, 230
Can he be an explosive athlete? He’s a good all-around football player, and he’s sound with almost no bust potential, but can he be a true difference-maker who blows up offenses? The better he does in the jumping and leaping drills, and the better he is in the short and agility ones, the more his stock will go up – the 40 time doesn’t really matter. 

2.Benardrick McKinney, Mississippi State 6-5, 249
Can he move fluidly? He’s not really built like an inside linebacker, and some are going to want to put him on the outside or inside in a 3-4 scheme, but he’s a leader and a main man for the middle. He can’t be stiff and he can’t run like the tall, rangy player he is. He has to be agile. 

4. Paul Dawson, TCU 6-2, 230
Able to play anywhere in a linebacking corps and be a playmaker. Really quick and really athletic, he can move around and be disruptive, but he has one big question mark among the scouting community – his attitude. He’ll have to ace the interview process to get past character concerns. 

5.Taiwan Jones, Michigan State 6-2, 252
Can he move at all? He’s as strong as they come when things are funneled to him, but his game is all about power. He has to look agile and he has to appear fluid to up his stock. He’s a true middle linebacker, but he can’t look like it. 

6.Ramik Wilson, Georgia 6-2, 237
It will do him a boatload of good to come up with a great bench and to appear physical. He’s not big enough and he’s not that great in coverage, but the biggest question mark is his toughness against the bigger running games. He has to look like someone who can blast away. 

7. Hayes Pullard, USC 6-1, 235<
Is he just an athlete or can he bring the thump on the inside? He’s not going to be for every style, and he could put up huge stats in the right system, but can he be a physical presence? Does he have the type of attitude that’s going to convince coaches that he’s going to be the alpha-male? 

8.Stephone Anthony, Clemson 6-3, 245
Be quick. He’s a good, fast, aggressive hitter and moves fine for a player of his size, but he needs to be good in coverage. He’ll look fine in shorts and he should build off a great Senior Bowl week, but his times in the short drills need to be excellent to show that he can keep up on third downs. 

9. Jordan Hicks, Texas 6-1, 234 
The physical needs to be clean. He’s a good all-around prospect and he’s going to be everything a team wants, but can he stay healthy? He missed way too much of his career, and while that doesn’t necessarily make him injury-prone, he’s been worn down. 

10. Trey DePriest, Alabama 6-2, 250
He has to be athletic and he needs to move well. Everyone loves his hitting ability, and everyone is going to like him against the power running games, but he needs to run better and he has to appear to be more of a playmaker outside of the box. Can he cover anyone? Can he be a pass rusher? That only comes out if he can run. 

11. Mike Hull, Penn State 6-0, 232
Something about him has to be special to overcome his lack of size and his mediocre quickness. He’s a good hitter and he can move just enough to be fine inside, but if he’s going to be versatile in any way, he needs to be fluid. His workout has to standout with one great thing a scout can sell. 

12.Zach Vigil, Utah State 6-2, 240 (Not Invited)
Everything looks great on tape and everyone wants players like him, but does he have the raw speed? Does he have the functional strength to go along with the football pop? He needs to be the athlete to go along with the on-field production. 

13. A.J. Johnson, Tennessee 6-2, 245
(Obviously, the ranking is based on him being able to play and if he’s cleared of all charges.) Character, character, character. He’s not an elite athlete and he’s a big-tackle player because he seems to read everything correctly, but he’s not a blazer. He surrendered himself on charges of aggravated rape, and while he maintains his innocence, he’s not draftable until the situation is played out. 

14. Ben Heeney, Kansas 6-0, 230
Everything is there except NFL talent – something about his workout has to change that. He’s not big, he’s not fast, and he’s not athletic, but he’s a baller. Now he has to show the scouts that he has the potential and the upside to be a starter. That happens with a great weekend. 

15.Amarlo Herrera, Georgia 6-2, 231 
Is he tough enough? He’s a good stat defender and he should run well and move just fine, but he has to come up with a strong bench and look nasty in the more physical drills. He’s not a blow-up hitter against the powerful backs, so if he can show raw strength, he’ll up his stock. 

16. Damien Wilson, Minnesota 6-2, 240
With good size, nice tape, and enough bulk to be a true middle linebacker, he has everything except for next-level quickness and athleticism. He has to give the scouts something to go off of – he has to look like a defender who can play in a few different spots. 

17.A.J. Tarpley, Stanford 6-2, 241 (Not Invited)
When he gets his chance, he can’t be slow. He’s a smart, instinctual defender who’s always around the ball and always making plays, but to be drafted he has to show good lateral quickness and moves. He can’t be stiff. 

18.Bryce Hager, Baylor 6-2, 235
Too small, too slow, and not explosive. He gets around the ball well and he’s decent in pass coverage, but will he be manhandled at the next level? There has to be something about his workout that stands out as something NFL-worthy. 

19.Quayshawn Nealy, Georgia Tech 6-1, 235 (Not Invited)
A very, very good college player and a great worker with the smarts to be the leader of a defense, he doesn’t have the athleticism to overcome his mediocre size. In his workouts he has to be physical, but more than that he has to be quick. 

20.Aaron Davis, Colorado State 6-0, 220
Way, way, way too small, if he doesn’t come up with a lights-out workout in the quickness drills, he’s probably not going to be drafted. He could turn into a great special teamer and reserve, but to be a starter, speed counts.