Deciding where college tackles fit on NFL offensive lines is no simple task

Doug Farrar and Greg Cosell discuss the difficulty of projecting college offensive tackles as guards and size up top prospects Brandon Scherff and La'el Collins in their latest NFL draft podcast.

The two best rookie guards of 2014 were tackles on their college teams. Cowboys right guard Zack Martin was Notre Dame's starting left tackle for three seasons, but his relatively limited athleticism projected him better as a guard. At the Senior Bowl, Martin lined up at guard and impressed the league enough for the Cowboys to take him with the 16th overall pick in the draft, marking the third time in four years that Dallas took an offensive lineman in the first round (Tyron Smith and Travis Frederick in 2011 and 2013, respectively). Martin was plugged in at right guard and immediately became the power pointman of an offensive line that re-defined the Cowboys' running game, paving the way for DeMarco Murray to lead the league with 392 carries, 1,845 yards and 13 touchdowns.

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The Browns face discouraging early returns on their two first-round draft picks in 2014—quarterback Johnny Manziel and cornerback Justin Gilbert are works-in-progress, at best—but they got it right in the second round when they selected Nevada tackle Joel Bitonio with the 35th pick. Like Martin, Bitonio had started his career taking snaps at guard but became the Wolf Pack's starting left tackle in 2011 and never relinquished that job. Bitonio had the athleticism to play left tackle in the NFL, but his relatively short arms presented an issue, and the Browns saw him as their left guard of the future, lining up between two Pro Bowl-level players in left tackle Joe Thomas and center Alex Mack. As it turned out, the future was now for Bitonio; he excelled in his new role from the start, and there are some who believe he was even more effective than Martin was.

It's a question personnel people have to ask themselves every draft season: Are the best tackle prospects better staying put or moving inside? It's fairly common to take tackles with shorter arms, thicker midsections and less impressive movement skills and kick them in to the guard position, but the successful transitions are about more than taking a pudgy guy and changing his roster designation.

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As Greg Cosell of NFL Films and ESPN's NFL Matchup said in our most recent draft podcast, the evaluation process for NFL tackles is far from a uniform template, which complicates matters in studying the draft's top offensive tackle prospects.

"It's a great question, but it's multi-faceted," Cosell said. "If you think about the NFL—and that's what we're doing, we're projecting these players to the NFL—there are a number of tackles in the NFL, even left tackles, if you were evaluating them now ... you might say, 'They're not really NFL left tackles, but they're playing left tackle in the NFL.' You could argue that Andrew Whitworth, who is a very good NFL left tackle, fits that category. There are others who aren't dancing bears. And I think when people think of left tackles, they like to think of really good athletes with really light, quick feet. But there just aren't that many Walter Joneses and Orlando Paces out there."

[daily_cut.nfl draft]Whitworth, who has alternated between guard and tackle throughout his nine seasons with the Bengals, gave up the fewest total pressures of any starting left tackle in 2014, per Pro Football Focus: no sacks, one quarterback hit and eight quarterback hurries. Whitworth was able to do this without excellent speed or an optimal kick-step in pass protection because he's an adept technician and an intense competitor who understands leverage and angles.

Whitworth is proof positive that not every successful NFL left tackle looks like a successful NFL left tackle. Iowa's Brandon Scherff, who stands 6'5" and weighs 319 pounds, could go either way. He may not be agile enough for teams that feature a quick-passing offense with fewer in-line tight end and multiple protections, but a balanced team like the Bengals—who found different kinds of value in Whitworth—might see him as the perfect edge protector. Like those before him, Scherff benefited from instruction at Iowa that is rich in fundamentals. It makes him more pro-ready, but he's also been hit with the low ceiling label.

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"You have to think when you watch a guy play ... let's take Brandon Scherff," Cosell said. "He's typical of this Iowa line of left tackles over the years. Bryan Bulaga came out of Iowa, he's playing right tackle for Green Bay. Riley Reiff came out of Iowa, he's playing left tackle for Detroit. When I look at Brandon Scherff, I would not say that he's a dancing bear. If you're looking for that ideal left tackle series of traits, I don't think he's that guy. But that doesn't mean that he can't play left tackle in the NFL, depending on what team takes him, and how that team runs an offense."

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Most agree that the top two tackles in the 2015 draft are Scherff and LSU's La'el Collins. Collins is a different player—at 6'4" and 305 pounds, he plays with tremendous in-line power and strength. But he'll lunge at targets in space, he tends to let defenders roll off him because he has difficulty sustaining blocks and he may not be quick enough to adjust to inside counters and certain speed moves.

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"I made the point in my notes that he was a badass as a run blocker," Cosell said. "And that's kind of what he is. But I think overall, he does have a desirable combination of natural power and athleticism. He took defensive linemen to the ground. He stayed on them. He was explosive off the ball. Now, you could also make the point that there were times when he fell off blocks. He's clearly comfortable and powerful and explosive as a run-blocker. That's the strength of his game. But he also has natural athleticism where he could work as a left or right tackle. If you're delineating between positions, you'd probably look at him as a right tackle or left guard."

In the end, it's the scheme fit that will make the decisions for Scherff, Collins and every other potential hybrid lineman in this draft class. These are special players, but the teams that draft them will have to do their homework to understand and implement the best strategies for their individual talents.

To listen to the entire Greg Cosell podcast on the 2015 class of offensive linemen, click below.