MINNEAPOLIS, MN - DECEMBER 1: of the game on December 1, 2016 at US Bank Stadium in Minneapolis, Minnesota. (Photo by Hannah Foslien/Getty Images) *** Local Caption *** =m#3;=v#3

Mel Kiper details the Cowboys’ biggest question mark following last year’s outstanding draft class

The best player in the draft may not have even seen the field yet

No doubt 2016 was a great draft, by any measure, for the Dallas Cowboys. Anytime you pick up a franchise quarterback in the fourth round (Dak Prescott) and a stud running back in the first (Ezkiel Elliott) that will power your team for years, that's a winner.

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But, ESPN draft guru Mel Kiper (inside access required) still gave the Cowboys an overall draft score a 'C,' and says its future success relies on one player - Jaylon Smith.

Smith, from Notre Dame,  was a sure-fire first-round pick before he suffered a knee injury that threatened his career. He looks like he's on the mend now. Still, here's what Kiper had to say:

Again, this is the best player in the draft if he's healthy, but what he'll become still remains a mystery, and that's a huge bet Dallas placed knowing its defensive personnel was a problem and will be again in 2017.

Kiper also noted that fourth-round pick Charles Tapper, the defensive end from Oklahoma,  didn't see the field because of a back injury.

Given Dallas' defensive woes - the Cowboys have lost several players from that unit in free agency this season - it makes it even more important Smith and Tapper make it back on the field.'