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. Amari Cooper, Alabama 6-1, 210
Catch everything. He can’t give the scouts any reason to go negative – he’s already loved across the board and seen as a can’t-miss. His hands are fine, but this is where he has to separate himself from the pack and look like the true No. 1 wide receiver. He can’t be 4.6 in the 40, and he has to grab everything in the passing drills. Don’t force the GMs and scouts to give excuses. 

2. DeVante Parker, Louisville 6-3, 211
Don’t be really, really slow. Amari Cooper might be seen as the first receiver off the board, but Parker is bigger and could be every bit the true receiver with a little time. However, he’s not a blazer and he’s probably not going to come up with eye-popping numbers, and everyone knows it. A good run or a quick shuttle time could be all he needs. 

3. Kevin White, West Virginia 6-3, 210
Is he quick? He looks right, should be great in the leaping drills, and he has the hands to be a special receiver who gets top 15 consideration with a good workout. Quietly, some are talking about him as possibly the first receiver taken off the board, and if he comes up with a great 40 time, look out. Some are looking for reasons to take him before Amari Cooper and DeVante Parker. 

4. Jaelen Strong, Arizona State 6-3, 215 
Don’t be slow. With his size and his fight and his overall potential, he’s seen as a bit of an unfinished product with a high ceiling. However, he can’t hover around the 4.6s and needs to be somewhere around 4.5 while looking quick and athletic. He’s already a scouting pet project guy, but he could slip into the first round with a great workout. 

5. Phillip Dorsett, Miami 5-10, 183
Bench press really doesn’t matter for a wide receiver, but if he can at least be a wee bit strong to go along with his speed – he’s in the mix to be the fastest player in Indy – he might show off that he’s not just a wispy speed receiver. He has home run hitting ability that’s missing from most of the top receivers, and if he can do more than run fast, then look out. 

6. Nelson Agholor, USC 6-1, 190
4.5 is okay, 4.4 would do wonders. Scouts can get past receivers who aren’t flashing sub-4.4s, but Agholor doesn’t have the body or the strength to be a do-it-all No. 1 NFL target if he doesn’t show off the raw speed. The fear is that he can be erased too easily – he has to show the athleticism to negate that. 

7. Tyler Lockett, Kansas State 5-11, 175
He has to be really, really quick. He’s a tremendous receiver, and he can be a great return man, but he’s not big and he can be shoved around. He’ll have to make his money on speed and quickness, and he has to be one of the top Combine warriors. 

8. Rashad Greene, Florida State 6-0, 180
Everyone needs a great 40 time, but Greene has to blaze away to be seen as a possible deep threat. At the moment he’s considered more of a No. 2, athletic receiver who can get open and keep the chains moving, but he wants to be dangerous. 

9. Devin Smith, Ohio State 6-1, 199
Blow up the Combine. He might come out of Indy with a pitch perfect workout showing off great speed, fluid quickness, and good all-around skills. He’s not an elite receiver in terms of pass catching skills, and he’s never going to be a physical fighter, but he could be devastating. He needs to look the part. 

10. Sammie Coates, Auburn 6-2, 201
Nail the 40. He’s a potentially dangerous deep threat, and he’s not a polished receiver coming out of the Auburn system, but he has to be the one who takes the top off the defense. He’s not going to be a do-it-all, 75-catch receiver at the next level, but if he comes up with something special in his runs, all of a sudden he’s must-have No. 3 part of the puzzle. 

11. Dorial Green-Beckham, Missouri/Oklahoma 6-6, 225
His interviews had better be sincere and they’d better be believable. He has top-five overall pick ability and upside, and he could turn out to be the best receiver in the draft – he was better than you’d think at Missouri – but his character issues are going to drop him to potentially out of the first round. He has to prove he wants it. 

12. Tony Lippett, Michigan State 6-3, 185
Be fluid. He’ll make GMs and scouts happy with his size, his interviews, and his fight, but he might be a plugger receiver who’s a nice part of a puzzle rather than a go-to guy. Can he move? Can the things that made him great in college translate when he’s dealing with better athletes? He has to be as smooth as possible. 

13. Breshad Perriman, UCF 6-3, 214
He might need lots and lots of work, but he’s a speed/size/athlete prospect with a tremendous blend of tools and skills. Now he needs to show off that speed and athleticism to overcome some bad tape problems. He’s a producer, but he also makes too many mistakes. Even so, if he flies, someone will like what he brings to an offense. 

14. Ty Montgomery, Stanford 6-2, 220
The ball drills are usually overblown in Indy, but Montgomery needs to snatch everything and has to time in the upper half. He has the body-beautiful, and he’s a dangerous football player however he gets the ball in his hands, but he could fly up the charts if all of a sudden he’s seen as a pure wideout and not just a jack-of-all-trades. 

15. Jamison Crowder, Duke 5-9, 175
His leaping ability will be scrutinized. He’s not all that big, but he’s fast and he knows how to get himself open, but he has to come up with a big broad jump and nice vertical to make himself bigger. He’ll have to be fantastic in the quickness drills. 

16. Stefon Diggs, Maryland 6-0, 190
How far is he away from being 100% and back to his former self? He might be as tough as nails when it comes to playing through pain, but he’s not going to get physical and he’s been way too banged up. His production wasn’t anything good after he got hurt. 

17. Titus Davis, Central Michigan 6-2, 190
Does he have any speed? He’s a great football player, and he’s polished with No. 1 target ability, but he has to show off some wheels. He might not be an elite athlete, but if he comes out of the Combine with a 4.5, he becomes a possible mid-round pick. 

18. DeAndre Smelter, Georgia Tech 6-3, 222
How healthy is he? He’s big, he’s fast, and he started to turn into a hot prospect until he suffered a knee injury. He’ll end up being drafted on a guess with an ACL that still needs a few months to heal, but with time there’s great upside. Along with his knee, he has a bum shoulder that needs to be checked out, too. 

19. Justin Hardy, East Carolina 6-0, 188
The production was off the charts, but does he have the raw tools to match? He’s not big, he’s not all that fast, and he’s not going to blaze away, but he has to show off NFL athleticism. He’ll make a roster as a No. 3 receiver who can move the chains, but can he do more? 

20. Deontay Greenberry, Houston 6-3, 198 (Not Invited)
He should’ve been given an invite. He’s big with speed and production, but he’s not a physical target and he was a bit inconsistent. Even so, he has the NFL look, and not being in Indianapolis might not be that bad a thing – everyone will want to see his pro day. If he can somehow look tough and strong, he’ll up his stock in a big way. 

21. Antwan Goodley, Baylor 5-11, 220
Can he look like a natural receiver? Everyone will love his numbers, his speed and his quickness, but he doesn’t really look the part and he’s a bit of a scheme-friendly target. Hands are a question mark – he has to snag everything in the ball drills. 

22. Rannell Hall, UCF 6-1, 200
How quick is he and how good will his first 10-to-20-yard split be? He’s going to put up a great 40 time, but after getting everyone buzzing at the Senior Bowl, he has to keep rising up the charts. Just an okay college receiver – even with Blake Bortles throwing his way – he’s a project. 

23. Vince Mayle, Washington State 6-3, 219
He needs to show off his hands. Everyone will love his size/speed/athleticism combination, but he was a product of the system and wasn’t a natural receiver. If it’s possible to catch 106 passes in a season and still be seen as a project, that’s Mayle. 

24. Dres Anderson, Utah 6-2, 190
is his knee healthy? He’s not a physical player to begin with, and he’s not the most natural of receivers, but when he’s 100% he’s a speedster with a great upside. He has to somehow convince everyone that he’s worthy of a mid-to-late draft pick even though he’s not going to be ready to rumble for a while. 

25.Austin Hill, Arizona 6-3, 212 (Not Invited)
At some point he has to show off the speed and deep ability that made him such a dangerous prospect before his knee injury. He looked like a special receiver in 2012, and there’s still a thought that he might bounce back now that he’s a few years removed from his injury. 

26.Dezmin Lewis, Central Arkansas 6-4, 212
With phenomenal size and good athleticism, he’s a scout-sleeper who could become the talk of the drafting circles with a great Combine. Strong at the Senior Bowl, he looked as good as any receiver during the week. There’s always going to be a big question mark about his level of competition, but if he rocks in the 40, look out. 

27.Devante Davis, UNLV 6-3, 215
Was it just the quarterback? Davis fell off after the QB play slipped up last season, but he has to blow up at least one drill in the Combine to become a must-have get to go along with his size and physical play. 

28.Josh Harper, Fresno State 6-1, 185
Does he have the tools to overcome the lack of size? He’s not all that big, and he’s not going to kill it in the 40, so he has to be ultra-quick in the short drills and has to come up with a reasonable sprint. He’ll have to be as polished a route runner as he can possibly look. 

29.Deon Long, Maryland 6-0, 185
What is he? He’s not a speed receiver, and he’s not all that physical, and he’s got a few durability concerns after suffering a leg injury a few years ago. There’s nothing about his game that stands out at an NFL level. He has to somehow change that in workouts. 

30.Darren Waller, Georgia Tech 6-5, 241
What is he? Is he a massive wide receiver or is he a smallish tight end? A potential tools guy, he can come up with big pops when he has the ball in his hands and there’s a world of upside, but he needs time and the right coach. If he destroys the Combine, attitudes about him will change. 

31.Cam Worthy, East Carolina 6-2, 214
Don’t be slow. He’s a tough target with a good frame and he proved in college that he could come up with big plays, but he’s not a blazer. A 4.7 makes him a tough draft pick, but a 4.6 – yeah, that 0.1 matters – makes him an easier sell. 

32.Da’Ron Brown, Northern Illinois 6-0, 196
Few players could use a great 40 time more than Brown. He’s not all that big, and while he was physical and tough in the MAC, that’s not going to work at the next level. He needs to be around a high 4.5s or lower to even think about being drafted before the sixth round. 

33.Ezell Ruffin, San Diego State 6-1, 210
It’s really more about his pro day than it is the Combine, but he has to catch everything, no matter what. He doesn’t really have the right size, and he’s not going to blaze away, so he needs to be a possession receiver and he has to be ultra-reliable with anything that comes his way. 

34.Tre McBride, William & Mary 6-2, 205
Everyone wants to see the 40 time. He’s a big, strong, talented prospect with a ton of upside, but he didn’t always dominate the lower-level competition like he probably should’ve. If he’s able to come up with a special sprint, then all of a sudden he’ll get the buzz rolling for his pro day and private workouts. He could shoot up the charts in a hurry. 

35.Donatella Luckett, Harding 6-0, 210 
Be more than the speed guy. He’s an elite track star guy who can blaze away, but he’s still a D-II receiver. He’ll get drafted on wheels alone, but does he have the quickness to go along with the straight-line speed? He’s still an unknown considering the offense he played in, but he’ll have to sell himself as a kick returner. 

36.Chris Conley, Georgia 6-3, 205
Is he physical enough for his size? He’s not going to wow anyone with his workout, and he’s not a blazer, but if he comes up with a good 40, he turned into a possible fifth-rounder. If he can show some toughness in some way – a good bench? – his stock will crank up. 

37.Keith Mumphery, Michigan State 6-1, 211 
Is he athletic in any way – at least at an NFL level? He was a good, tough college football player, and he’s the type of receiver coaches will love to have, but he needs to be quick and can’t be lumbering. He’s going to have to fight is the numbers aren’t there. 

38. J.J. Nelson, UAB 5-11, 160
He had better be really, really athletic. There’s nothing to him – he’s way, way too slender – and he can be shoved around without a problem, but he’s a returner and he’s fast. He has to show the twitch and the quickness to be used in a variety of ways. 

39. Davaris Daniels, Notre Dame 6-1, 203 
He missed all of last year with the academic scandal at Notre Dame, and now scouts have to guess a bit. The interview process will be the big key – but he’ll be fine there – and the workout will have to show no rust. He needs to come out and run and workout like there’s something to prove. 

40. Kaelin Clay, Utah 5-10, 193
Really, really fast, he has to overcome his lack of bulk by flying through all of the drills. The quicker he is, the more he’ll be seen as a return man who could latch on also as a dangerous option in three and four-wide sets. 

41. Mario Alford, West Virginia 5-9, 177
Speed, speed and more speed – he has it – but is he able to show he can become an all-around receiver? He’ll have to make a roster as a kickoff returner and a slot target, but his speed and quickness have to be off the charts to become draftable. 

42. DeAndrew White, Alabama 6-0, 192
Is he durable at the next level? Almost never in one piece, he has the quickness and he can run well, but the physical will be everything to his draft status. The one-time star recruit isn’t the same player he was before all the injuries. 

43. Geremy Davis, Connecticut 6-3, 216
Not big enough to be an H-back or a tight end, and not fast enough to be a receiver at the next level, he has to find a position and a role. There’s no excitement to his game looking forward, and he has to somehow look and appear stronger and tougher as a blocker. 

44. Jordan Taylor, Rice 6-5, 210 (Not Invited)
Intriguing because of his size and his length, he came up with big numbers, but will his game translate? He’s not a blazer, and he can be pushed around, but he has the potential to be a good, sound route-running No. 3 or 4 option with a few good workouts. 

45. Christion Jones, Alabama 5-11, 187
All that matters is his ability as a kick returner, making the short and quickness drills everything. He’s not an NFL wide receiver, but he could see time on an offense if needed. He has to be ultra-athletic to be draftable.