Mel Kiper's Big Board and position rankings: Top 2018 NFL draft prospects

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With the NFL combine over, teams have begun setting their 2018 NFL draft boards. And with a little more than a month until the Browns are on the clock, the first round is becoming clearer.

It's time for an updated Big Board, which is my ranking of the top 25 prospects for the Class of 2018, along with updated position rankings, which are my top 10 prospects at every position. I'll have my Mock Draft 3.0 next week.

Click here to go to the position rankings, which are listed after the Big Board.

Note: One asterisk denotes the player is a junior, and two asterisks denote the player is a redshirt sophomore for the 2017 season.

Quick links: Kiper's Mock 2.0 | Re-grading 2017 draft | Full draft order

1. *Saquon Barkley, RB, Penn State

Previous rank: 1

I don't see Barkley moving out of the top spot here, and he's a lock to be picked in the top five. His testing numbers at the combine -- 4.40 40-yard dash and 41-inch vertical -- were elite at any size, much less a 6-foot, 233-pound back. Barkley plays with tremendous balance, a great lower body and quick feet. He's a stellar runner both inside and outside the tackles, and he showed in 2017 that he's a true three-down back. He had 54 catches after having 48 combined in his first two seasons at Penn State. Barkley is a special talent.