With the NFL season over and the offseason upon us, we've been covering Mike Mayock's rankings at every positionand breaking down the Bengals' need at each. So far we've covered quarterbacks and tight ends, offensive line, running backs and wide receivers, and the defensive front seven.

To wrap things up, we're looking at the defensive backfield. The Bengals have four defensive backs, two of which made the 2016 Pro Bowl, hitting free agency in 2016: Reggie Nelson, Adam Jones, George Iloka and Leon Hall. As we don't yet know who will be back, it's hard to say how big of a priority cornerback and safety will be for the Bengals in this year's draft But, if even one of those players leave, a defensive back could become a bigger priority early on in the draft. Who are the top prospects at those positions? Let's take a look.

Cornerbacks

The Bengals have recently invested in a pair of first round picks at cornerback with Dre Kirkpatrick (2012) and Darqueze Dennard (2014). Therefore, it seems unlikely that the team would look at some of these prospects in the first round. However, with Jones and Hall both potentially leaving in free agency, it would make sense for the team to look at this position as early as the second round.

1. Jalen Ramsey (Florida State)

Jalen Ramsey has the strange distinction of being considered a top five draft pick, a region where defensive backs are not generally found. He's got the brain, athleticism, and success rate to suggest that he could be the next big thing in the NFL, but questions about his size and balance persist. He's more of a slot corner, based on his style of play. But, he has the talent to make it as an elite shutdown corner with the right training and mindset.

2. Vernon Hargreaves (Florida)

Hargreaves is a competitor. There's just no two ways about it. There are a few questions about his size, but the fact of the matter is, he's going to step on the field and wear down any receiver that dares to challenge him. The only hope that opposing wide receivers have against him is to jump over him for the catch and physically overpower him to avoid a tackle. He's a sure first round prospect.

3. Mackenzie Alexander (Clemson)

Depending on who you ask, Alexander might be the best cornerback in the draft, and he knows it. He's got the NFL mindset and talent to stick to receivers like glue. He's also short and takes a little longer than you'd like to adjust to his man's route. But, once he figures it out, you won't shake him off. As long as he can keep his cockiness in check at the NFL level, he's a future star. He won't fall below the very early second round.

4. Eli Apple (Ohio State)

Health and attitude problems gave Apple a rough freshman year at Ohio State, but, the main thing everyone is talking about is what he did after he pulled things together. As long as the defensive line doesn't let the quarterback extend the play too long, he's explosive enough that he'll make a quick play leaving teams frustrated and scrambling. However, once he has to cover for an extended period of time he can lose his focus and start grabbing jerseys. He could be a star on the right team, but his drawbacks could relegate him to the second round. He has been mocked to the Bengals and Steelers (who pick back-to-back) in the first round of varying mock drafts.

5. Cyrus Jones (Alabama)

About Jones, an unnamed NFL executive told Mayock, "He may need to get his Twitter game in check." On the field, he's versatile enough to thrive in the nickle, but his less impressive speed and size could cause him to only fit well in certain NFL systems.

One system he could thrive in is Paul Guenther's disguised man coverage scheme. Jones would essentially be playing a similar role to what Leon Hall has been playing in Guenther's defense. There's no guarantee that the Bengals are even looking at him. But, as a projected fourth round pick, he seems to fit perfectly with the Bengals' plans. Jones is also a punt returner so he could be an interesting option to replace Adam Jones, if he were to leave in free agency.

Safeties

I won't sugar coat it. It's very difficult to see both Reggie Nelson and George Iloka returning next season. As great as Nelson played, he's 32-years-old and not getting any younger. Iloka is 25 and has recently been a reliable starter, albeit less explosive than Nelson in 2015. As good as Shawn Williams played in his few opportunities last year, I would venture as far as to say that safety could easily be a target for the Bengals in the earlier rounds of the draft, assuming either Nelson or Iloka leave in free agency.

1. Karl Joseph (West Virginia)

This year isn't a particularly great year for safeties. Had it not been for his ACL tear that caused him to miss half of his senior season, Karl Joseph would have been a sure first round pick. It has been suggested that Joseph could fall as far as the fourth round because his style of play and being very injury-prone. However, any team willing to take a chance on his pure athleticism, football character, and NFL-level discipline could be greatly rewarded with a future star safety.

2. Von Bell (Ohio State)

Bell will likely be the most sought-after pure safety talent in the draft this year. His championship swagger and his extensive playing experience at Ohio State are tough to look past, but his performance drop off in 2015 could have him falling into the second round. That's not to say that 2015 was a bad year for Bell. It's just that he only finished as second team All Big Ten, as opposed to the incredible play that he displayed in the 2014 Orange Bowl and the 2015 BCS championship.

3. Darian Thompson (Boise State)

The Mountain West's all-time interceptions leader (19), Thompson earned four All-America nods and was named to All-Mountain West First Team and was a Jim Thorpe Award semifinalist. Thompson has the timing and soft hands to make tons of plays at the NFL level. He needs to work some on his awareness to be a consistent force, but he could be a fantastic replacement for Nelson's production, were he to leave in free agency. Even if the Bengals keep Nelson, Thompson can sit behind Nelson and learn while Nelson finishes his career.

4. Miles Killebrew (Utah State)

A strong safety projected to fall as late as the third round, Killebrew is a perfectly built destruction machine. He knows how to take down his targets with drive and without hesitation or remorse. His football instincts are lacking and he also has a tendency to lose track of his man in coverage. It's unlikely that the Bengals are looking at him because his position and style of play are extremely similar to Shawn Williams, who isn't going anywhere.

5. Jeremy Cash (Duke)

Jeremy Cash is fairly similar to Von Bell in terms of draft stock, yet very dissimilar in terms of impact and style of play. Cash doesn't cover man well and is slow to fall into zone coverage. However, he is particularly adept as a run stopper. He has deceptive closing speed, meaning he has a great chance of bringing the ball carrier down every time. The problem is, it's too easy to throw the ball past him. He's likely to be relegated to more of a nickel role in the NFL, much like Taylor Mays. As a projected second round pick, he doesn't really fit the Bengals' current scheme enough for the team to consider him.