Headed into the 2015 NFL draft, cornerback looked like a position the New England Patriots could address as high as the first round. Even when the value didn't fall right in the early rounds, most figured the Pats would take a flier at some point early in Day 3.

However, Bill Belichick and Co. bypassed the position entirely until the 247th overall pick, when they nabbed Marshall's Darryl Roberts.  For the Patriots, Roberts could be worth the wait. I've seen Marshall as one of the most underrated cornerback prospects in this draft, and mocked him to New England in my final Day 3 projections this morning.

So what is it about Roberts that could make him the next seventh-round steal in Foxborough? Let's take a look at how Roberts could defy the odds and carve out a considerable role in the secondary.

What Roberts Brings

At 6'0" and 182 pounds, Roberts is a bit lean to play the outside cornerback spot at the pro level, despite adequate height. Nevertheless, few corners are more athletic, sustaining a theme in the Patriots' late-round picks this year. Though he was not invited to the scouting combine, Roberts' pro day provided some eye-opening testing numbers:

For reference, that three-cone time would have been second-best among all corners in Indianapolis, while his short shuttle time would have topped the position. Pro Football Focus, relying on their in-house grading system rather than mainstream scouting consensus, actually suggested that the Patriots should draft Roberts in the second round. In a separate piece, PFF's Gordon McGuinness highlighted Roberts as one of the position's top sleepers:

If you listened to our Podcast breaking down the cornerback class, you’ll know that this is a guy that Sam Monson really likes. It’s easy to see why too, with Roberts showing an ability to handle anything the coaches asked of him. On top of that he showed great balance and reactions, reading moves by wide receivers very quickly.

If there is a concern here, it would be that I would like to see him attack the ball more on deep passes, instead of waiting for the receiver come down with the ball before trying to rip it free. He’ll see plenty of physical wide receivers on Sundays in the NFL, so he’ll need to be ready to adapt his game to handle that.

McGuinness also noted how Roberts conceded a paltry 0.88 yards per coverage snap, one of the 20 best marks among FBS corners. With excellent fluidity and long arms, Roberts is able to shut down many short and intermediate routes using his rare combination of speed and length.

Roberts probably isn't a fit outside—his biggest weakness is his tendency to panic downfield and get handsy, which will lead to plenty of penalties in the pros if he does not improve that technique. Still, with the ability to play press coverage, Roberts could allow the Pats to preserve their scheme from last year.

How Roberts Fits

Obviously, a single seventh-round pick does not tip what kind of coverage scheme the Pats will utilize next season. But given Roberts' strength in press, it seems as though Belichick would like to preserve some of the same principles that the secondary used with great success in 2014. Roberts isn't the centerpiece of that decision, but pre-draft metrics suggest that he holds significantly higher upside than the average Round 7 flier:

Roberts will probably challenge Kyle Arrington and possibly Robert McClain in the slot. Those unspectacular veterans are both better suited for off coverage, so while Roberts could probably fit in that kind of scheme with his quickness, it will be interesting to see if the coaching staff lets him be as physical as the Marshall staff did.

In terms of skill set, Roberts probably aligns closer to the Bradley Fletcher-Malcolm Butler crowd, which would prefer to play press, than the Arrington-Logan Ryan bunch, which would indicate zone. This isn't necessarily an either-or choice—the Patriots will obviously play both in 2015—but if he does succeed, Roberts' skill set would be maximized in a man coverage scheme that allows him to smother smaller slot receivers.

One other avenue onto the roster: Roberts is an above-average special teams player and has the speed to contribute in coverage teams there. He's now the third player who should contribute immediately in the third phase (along with Matthew Hull and Joe Cardona), an indication that Belichick might be tiring of some of the younger players on the roster who have yet to break through beyond special teams.

Bottom Line

Most Patriots fans will not be happy that the team invested just one seventh-round pick in the cornerback spot. Now that free agency and the draft have both passed, we can definitively say that the defensive backs will face an uphill battle to succeed in 2015.

The Pats do have plenty of quantity at the position, though it's entirely comprised of replacement-level veterans (Fletcher, Arrington, McClain) or unproven youngsters (Butler, Ryan, Alfonzo Dennard). Roberts adds more strength in numbers there, which should make for one of the livelier training camp competitions this summer.

There should be plenty of enthusiasm surrounding Roberts, as he has a legitimate chance to join New England's list of seventh-round steals. Between David Givens, Julian Edelman and Matt Cassel, the Pats have had plenty of success generating huge returns on tiny investments. It's obviously too soon to add Roberts to that list, but he's a big-time sleeper to watch at New England's weakest defensive position.