NFL Draft 2020: Who Is Isaiah Simmons?

Before he would play five positions on Clemson’s defense — sometimes in the same game, always to devastating effect — Isaiah Simmons had none. Many of the programs recruiting him didn’t know where, or how, he would fit. Even Clemson envisioned him only as a safety.

“You never guess a guy’s going to turn into a 240-pound monster,” Brent Venables, Clemson’s defensive coordinator, said in an interview. “Didn’t necessarily see that.”

The only thing harder than projecting Simmons’s evolution into the N.F.L. draft’s best all-around defensive prospect, perhaps, has been discerning his whereabouts before a snap.

Simmons, who stacked a 4.39-second 40-yard dash at the N.F.L.’s scouting combine with a 39-inch vertical jump and an 11-foot broad jump, aligned at slot cornerback, edge rusher, linebacker and both safety spots last season. He played at least 100 snaps at those five positions, according to Pro Football Focus, and finished with 16.5 tackles for a loss, eight sacks, eight pass deflections and three interceptions.

“In a league that doesn’t have a lot of margin for error when it comes to roster management,” Venables said, “I think you immediately get more than one person.”

In that, the 6-foot-4 Simmons counterbalances the raft of hybridized offensive players permeating the N.F.L. He has the build, speed and length to counter players like San Francisco 49ers tight end George Kittle and Carolina Panthers running back Christian McCaffrey, who often cause mismatches for defenses. Modern defenses prioritize pressuring the quarterback and stopping the pass, and Simmons can do both.

For Venables, one of Simmons’s many highlights lingers longest. On fourth-and-3 from Clemson’s 34-yard line, in the second quarter of the Tigers’ College Football Playoff semifinal victory two seasons ago against Notre Dame, Simmons lined up in man coverage opposite receiver Miles Boykin, who ran a fade up the right hash. Simmons recovered quickly after a brief stumble off the line, shadowed Boykin for about 15 yards and, instead of clumsily running into him, reached around him to deflect the ball with his left hand.

It was, indeed, an excellent play — made by a former safety playing cornerback who last season was selected as college football’s best linebacker. Where he plays in the N.F.L. is intriguing — linebacker, most likely — but, in the end, irrelevant. For when Simmons was asked his position at the combine, he offered but one word: defense.