Over the next several months, the rosters of all 32 teams will begin to take shape for the 2019 season. In this series, NFL.com writers and analysts look at the best players available in the 2019 NFL Draft, free agency or via trade (limited to players who are reportedly available or open to being dealt) at the following positions: quarterback, running back, defensive back, pass rusher and receiver. Today, Gil Brandt examines the top 10 defensive backs worth pursuing.
1) Earl Thomas, free agent: From a strictly Xs and Os standpoint, Thomas is the best safety available in the 2019 offseason. His recognition skills are outstanding, as evidenced by his 25 interceptions between 2010 and 2017, which is the second-highest total among all safeties in that span. The concern stems from the fact that he missed 19 of 48 games over the past three seasons with the Seahawks, including 12 in 2018 after suffering his second serious leg injury in as many years. That, along with his comments about potentially retiring following the broken tibia he suffered in December of 2016, could give potential suitors pause. He's publicly lobbied to join the Cowboys before, but if Dallas is unable to fit him into its long-term payroll picture, San Francisco could be an intriguing destination. The 49ers need more playmakers in the secondary after recording an unbelievably low interception total of two in 2018.
2) Ronald Darby, free agent: The dearth of established top-tier cornerback talent on the market puts Darby in excellent position to cash in, provided he's fully recovered from the ACL tear that ended his 2018 season in November. Despite playing in just nine games, Darby led Philadelphia in passes defensed (12). Plus, the former Bills second-rounder is still only 25. Frankly, I'm not quite sure why Buffalo was willing to trade him to Philly back in 2017.
3) Deandre Baker, draft prospect: Baker capped his Georgia career by capturing the 2018 Jim Thorpe award, given to college football's best defensive back. He can play all three positions in the secondary and excels at press coverage. If his time in the 40-yard dash at the NFL Scouting Combine demonstrates an ability to keep up with NFL-caliber wideouts, that would go a long way toward cementing his pre-draft stock. He could be a smart pick for the Broncos, who will be looking to replenish their secondary, especially if Bradley Roby leaves as a free agent.
4) Landon Collins, free agent: Collins figures to be a candidate for the franchise tag. He was used primarily as a box safety and slot corner in new coordinator Jim Bettcher's defense last year, before landing on injured reserve last season with a shoulder issue. Those questions aside, Collins reminds me of six-time Pro Bowler Eric Weddle. He knows how to get the rest of the defense lined up correctly. He's not the fastest guy in the world, but he knows how to play -- his ability to understand opposing offenses is what makes him valuable to whichever team ends up with him. Put simply, he's a football player.
5) Greedy Williams, prospect: LSU has a long history of producing top-flight defensive backs, and the semifinalist for the 2018 Jim Thorpe award is no exception. He has the size (at 6-foot-2 and 185 pounds) and fluidity to stick with big-bodied wideouts, plus the arm length to help him defend passes. It also looks like he runs well, though we'll learn more about that at the combine in Indianapolis. Like fellow former Tigers Donte Jackson (picked 55th overall by the Panthers in 2018) and Jamal Adams (picked sixth overall by the Jets in 2017), Williams looks like someone who can step in and help a pro team right away.
6) Tyrann Mathieu, free agent: The Honey Badger gambled on himself in 2018, and now he should be able to land a deal that is considerably more lucrative than the one-year, $7 million pact he inked with Houston last offseason. Still just 26, Mathieu has range and can cover in the slot. Plus, he seems to have shaken the injury bug that dogged him earlier in his career, starting all 16 games in two straight seasons. Mathieu might be small (5-9, 185 pounds), but he has a great nose for the football -- he's the kind of guy who seems to always be picking up the key fumble or making the crucial tackle. In 2018, he recorded 89 tackles, three sacks, eight passes defensed and two picks.
7) Bryce Callahan, free agent: Slot corner doesn't always get the attention it deserves as one of the most difficult positions to play. To be an effective slot corner, you need to be able to play the trail position in coverage and tackle well. Callahan could set the market for the players who man this unique spot on the field, following a breakout campaign in Chicago. The former undrafted free agent allowed just 0.69 receiving yards per coverage snap in the slot, which was the lowest mark among the 30 cornerbacks who played at least 200 coverage snaps, according to Pro Football Focus. Callahan did suffer a season-ending broken bone in his foot in Week 14, but I'd anticipate that he'll be ready for 2019.
8) Pierre Desir, free agent: The Colts were among the NFL's biggest surprises in 2018 -- and the same could be said for Desir, the fifth-year pro who flourished in the Tampa 2-style defense implemented by coordinator Matt Eberflus. Desir started almost as many games last season (12) as he did in his first four NFL seasons (13), with the Browns, Chargers and Colts. He also recorded 79 tackles, which nearly matched his career total entering 2018 (81), and, perhaps more importantly, proved he could hold his own against some of the NFL's top wideouts. Consider the work he did on Texans receiver DeAndre Hopkins, who was limited to nine catches for 73 yards in Indianapolis' wins over Houston last December and in the playoffs.
9) Lamarcus Joyner, free agent: On a Rams defense loaded with big names, Joyner is often overlooked. While Joyner did have a career-high 78 tackles last season after being retained by Los Angeles via the franchise tag, he didn't perform at the same level he did in 2017, picking off just one pass and notching just three passes defensed. The question is, why did he slow down? Joyner provides some flexibility, with his ability to play both free safety and slot corner, but Los Angeles is also set to return Aqib Talib and Marcus Peters, and I would expect Joyner to be playing elsewhere next season.
10) Joejuan Williams, draft prospect: Fellow SEC cornerbacks Baker and Greedy Williams have received more pre-draft hype, but Joejuan Williams could end up being the better NFL player in the long term. The Vanderbilt product is a big-bodied corner, checking in at 6-3 and 208 pounds -- 23 pounds heavier than Greedy. He's a tackler who plays the ball, as his SEC-high 14 pass breakups in 2018 will show you. I don't think he'll have to wait until Day 2 to hear his name called.
Follow Gil Brandt on Twitter @Gil_Brandt.