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The 2018 NFL regular season ended Sunday night, but fret not: It's officially draft season. The work now begins in earnest of evaluating, grading and ranking the top players in the class—in fact, our NFL Draft 400 work started Monday morning while the New England Patriots were sleeping off their celebrations.

NFL Draft 400 is a project for which we write up 400 prospects complete with grades and pro player comparisons. To rank 400 players, you have to start somewhere. Generally, we start at the top and work down. That has led to an updated Big Board and a few key changes in the top 50 overall.

Why are there changes in February when the season ended a month ago?

Frankly, there isn't enough time from September to January to watch all the players. Seniors and underclassmen who we know will declare take priority, but in a year with 135 juniors entering the draft, it takes time to get all the film watched and reports written. It's not so much that players' stocks rise and fall in the predraft months, it's often that we're just getting caught up on film and that causes them to move.

Who are the big movers on the updated Big Board? Here are a few, plus some new names, before unveiling the top 50 below.

Alabama RB Josh Jacobs

It's unlikely a running back will be drafted in the top five picks this year, but Alabama's Josh Jacobs is worth it. Jacobs, who sits at No. 5 overall on my board, has a mixture of power and speed that should excite NFL general managers. He's a more powerful version of Alvin Kamara with limited wear and tear, only carrying the ball 120 times as a junior and 251 times total in college in the deep Alabama backfield.

Iowa TE T.J. Hockenson

The gridlock at tight end is over. Iowa's John Mackey Award winner, T.J. Hockenson, has emerged as the best in this class. Hockenson has it all: He's more powerful and complete than teammate Noah Fant (while not as athletic) and is a better route-runner and more versatile than Alabama's Irv Smith Jr. Hockenson's ability to play as an in-line or flex tight end should cement his comparison to Travis Kelce.

Washington S Taylor Rapp

David Zalubowski/Associated Press

It's impossible to not fall in love with Taylor Rapp's tape. He's a great tackler in the open field with instincts and toughness and shows the speed and range to play in multiple alignments at either safety position. Rapp's football IQ and high character makes him the top-ranked safety on the new Big Board.

Kansas State OT Dalton Risner

Too many scouts look at Dalton Risner and immediately want to move him to guard or center. He's 6'5", 308 pounds with 10 5/8" hands and 34 1/4" arm length. Those are left tackle metrics. If you watch his tape and conclude that he doesn't have the foot speed or strength to play tackle, that's another thing, but he's not a small prospect. I would argue the tape also says he can play tackle at a high level in the NFL. Risner should be considered late in the first round if there is a run on linemen.

Florida Atlantic RB Devin Singletary

If Josh Jacobs comes off the board early in Round 1, Devin Singletary could be the belle of the ball in Round 2. He's quick—very quick—and has the hips and feet to beat defenders with excellent ability to cut and shake in the open field. Singletary is a dream fit for the Kansas City Chiefs or Philadelphia Eagles if they opt to go running back early.

The Scout's Report

—NFL Network great Daniel Jeremiah had an interesting note on Kyler Murray, the two-sport star from Oklahoma who was drafted ninth overall to play baseball by the Oakland A's in 2018 but has entered the NFL draft. Per Jeremiah, Murray could essentially pick his spot by telling undesirable NFL teams he would play baseball if they drafted him. By doing this, Murray controls his destiny. It remains to be seen if he'll actually do this, but he could.

—Dwayne Haskins is primed to be this year's "riser" after the NFL Scouting Combine. People around the league are raving about his arm talent, body and character. One high-level personnel man in the AFC told me he believes Haskins will be the player teams are trying to trade up for in the top 10 picks.

—Florida's Jawaan Taylor is another player exciting NFL scouts. The big Gators right tackle has excellent quickness and balance for a man who runs 335 pounds. He uses his length well and has shown experience cutting off pass-rushers on the right side. Don't be surprised if he's a top-15 selection.

—Where will Nick Foles land? Foles opted out of his contract with the Philadelphia Eagles, which would have paid him $20 million for the 2019 season, according to Ian Rapoport of NFL Network. The Eagles have one more play, which would involve using the franchise tag on Foles and then attempting to trade him. Foles would essentially be able to pick his next team, since he could opt to not sign the franchise tender if traded to a franchise he doesn't want to play for. It's a unique situation that can be a bit confusing at times, but right now it looks like Foles will be traded rather than become a free agent.

—Northwestern quarterback Clayton Thorson wasn't able to participate at the Senior Bowl due to an injury, but that didn't keep scouts from discussing his stock.

Denis Poroy/Associated Press

Thorson, said one noted quarterback evaluator with an NFC team, was held back by a poor supporting cast this season. "Put him on a team with a good offensive line and at least one playmaker and you're talking about him a lot more," the evaluator said. The NFL combine will be important for him, but Thorson has a chance to be a Day 2 selection.

The Big Board

It's time to update the big board after two weeks on the road evaluating at all-star games. Here's my most recent top 50:

1. Nick Bosa, EDGE, Ohio State

2. Quinnen Williams, DL, Alabama

3. Josh Allen, EDGE, Kentucky

4. Rashan Gary, DL, Michigan

5. Josh Jacobs, RB, Alabama

6. Devin White, LB, LSU

7. Ed Oliver, DL, Houston

8. Jonah Williams, OT, Alabama

9. Jeffery Simmons, DL, Miss. State

10. Greedy Williams, CB, LSU

11. Clelin Ferrell, EDGE, Clemson

12. Devin Bush, LB, Michigan

13. Montez Sweat, EDGE, Miss. State

14. Dwayne Haskins, QB, Ohio State

15. Byron Murphy, CB, Washington

16. Cody Ford, OL, Oklahoma

17. Brian Burns, EDGE, Florida State

18. Trayvon Mullen, CB, Clemson

19. T.J. Hockenson, TE, Iowa

20. Marquise Brown, WR, Oklahoma

21. Deandre Baker, CB, Georgia

22. Taylor Rapp, S, Washington

23. Noah Fant, TE, Iowa

24. Irv Smith Jr., TE, Alabama

25. Jawaan Taylor, OT, Florida

26. Jachai Polite, EDGE, Florida

27. Jaylon Ferguson, EDGE, Louisiana Tech

28. Andre Dillard, OT, Washington State

29. Yodny Cajuste, OT, West Virginia

30. N'Keal Harry, WR, Arizona State

31. Christian Wilkins, DL, Clemson

32. Deionte Thompson, S, Alabama

33. Daniel Jones, QB, Duke

34. Kyler Murray, QB, Oklahoma

35. Drew Lock, QB, Missouri

36. DK Metcalf, WR, Ole Miss

37. Hakeem Butler, WR, Iowa State

38. Dalton Risner, OT, Kansas State

39. Jerry Tillery, DL, Notre Dame

40. A.J. Brown, WR, Ole Miss

41. Elgton Jenkins, OC, Miss. State

42. Nasir Adderley, S, Delaware

43. Oshane Ximines, EDGE, Old Dominion

44. Rock Ya-Sin, CB, Temple

45. Johnathan Abram, S, Miss. State

46. Mack Wilson, LB, Alabama

47. Parris Campbell, WR, Ohio State

48. Mecole Hardman, WR, Georgia

49. Deebo Samuel, WR, South Carolina

50. Devin Singletary, RB, FAU

Parting Shots

6. Stock Up

Outside of the players moving up the board in the top 50 listed above, Buffalo's Anthony Johnson continues to push up the wide receiver rankings. Johnson, a senior, is a fade-route specialist with excellent awareness. He extends well to get the ball above his frame and has good size at 6'2" and 211 pounds. His tape doesn't show great explosiveness, so we'll be watching to see how he runs at the combine, but the combination of his Senior Bowl week and the traits seen on tape is exciting.

5. Stock Down

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Alabama's Deionte Thompson shot out of a cannon this season as a first-year starter who looked like the NFL's answer to the free safety position, but Thompson has since fallen down the board consistently. He struggled against Clemson in the national title game, showing a timid nature and slow instincts that weren't there early in the year. Whether he was dealing with an undisclosed injury or just struggling, Thompson didn't look right. There are also legitimate concerns about his body type and weight. He's very skinny throughout his body and was playing at an estimated 170 pounds this season. That won't cut it in the NFL.

4. Sleeper of the Week

Texas linebacker Gary Johnson didn't participate in any offseason all-star games and seems to be a forgotten man in the predraft process. That's a shame, because his tape shows an athletic, tough, smart linebacker who can play in the middle and handle the flow outside the hashes in the run game. He's agile enough to play in pass coverage too and was often asked to drop in zones or blitz. Johnson was suspended for a game this year after violating a team rule, but that's not reason enough for teams to forget about his ability.

3. NFL Scouting Combine

The NFL released the official scouting combine invite list on Thursday, with 338 draft-eligible players invited to Indianapolis for weigh-ins, drills, interviews and a load of tests. There will be a month of coverage on the event, but the first note is that 338 players isn't that many.

Sure, there are only 256 picks in the NFL draft, so there's an excess of players to evaluate. But consider that 135 juniors entered into the draft. The combine simply isn't equipped to handle the number of players teams must now evaluate.

Darron Cummings/Associated Press

My pitch to the NFL: Expand the combine to at least 400 players for 2020 and expand the NFL draft by one round (eight total) to bring the number of players drafted closer to 300. Underclassmen are entering the league at a record-setting pace, and the NFL's decision to ignore that isn't helping.

2. If you love Stick to Football and want to meet the crew, you have three chances in March to hang out with us. We're using a ticketing system for each, but it's free to sign up (and you get some free swag if you show us your ticket).

* March 2: Indianapolis at the NFL combine

* March 14: Nashville, Tennessee

* March 30: Kansas City Royals' weekend opener

1. Stick to Football has three new episodes this week. On Monday, Rutgers safety Saquan Hampton joined us, and we dove into trades we'd like to see this offseason. Wednesday's show featured Senior Bowl executive director Jim Nagy and our "Fixing the Giants" segment. Friday brought us David Sills V and the latest on Kyler Murray. Check out the podcast and subscribe if you haven't already. We will also post a ton of behind-the-scenes content on our Instagram page.

Matt Miller covers the NFL and NFL draft for Bleacher Report.