Not a lot went right for the secondary of the 2019 Detroit Lions. Though the unit started out the year as one of the most lauded in the NFL with some like PFF crowning Justin Coleman one of the best signings of the year. That praise died out swiftly and spectacularly.

Losing Quandre Diggs, a fan favorite, when viewed objectively at the time wasn’t that bad of a move. The Lions suffered defensive collapse after defensive collapse and it was just another move pointed to in a laundry list of reasons this team was failing.

There’s a lot more nuance to this unit than I first expected, so follow along with our final piece of our three part series looking at the 2019 roster.

Previously: The offense, The front seven

The corners

The Lions cut loose from everyone’s favorite punching bag, Teez Tabor, before the season began. He was Bob Quinn’s most obvious and biggest miss as a talent evaluator, but more importantly, it truly threw a wrench in figuring out exactly what it was Quinn wanted from his cornerbacks. Bringing in Matt Patricia didn’t do much to ease that confusion since Tabor was still here and the non-Darius Slay cornerbacks were such a hot mess. The ‘loss’ of Nevin Lawson also signaled a potential change in the personnel they were using going forward.

The additions and subtractions of the past two seasons have brought that far more into focus, and while it’s boring, it’s at least easy to understand. The Lions have favored players who are strong man coverage corners but who have shown the versatility to play in zone as well. So while they favor one, it isn’t to the detriment of the other. Pretty simple. Athletically at corner, Quinn has shown a preference for the same type of player he said he liked prior to drafting Tabor (when many stopped believing him), long, lean, and fast.

Where they’ve went wrong is that in asking their corners to cover primarily in man, they’ve put an extra emphasis on two things the Lions failed to do in 2019. The pass rush wasn’t able to create pressure fast enough to force throws earlier than the routes develop and the corners weren’t able to cover in man long enough to force the quarterback to hold onto the ball too long.

The Lions signed Rashaan Melvin hoping he could return to the form he displayed as a Colt in 2017 rather than his time as a Raider in 2018. Instead, he put up a career worst year. Matt Patricia liked corners who can tackle well and Melvin certainly did that having only missed two tackles all year. But as one of the worst cover corners in the NFL (which is pretty important) this signing was obviously a bust. Familiarity might see Melvin return, but I think it more likely we’ve seen the last of him.

Justin Coleman, as mentioned before, started out the year on fire, but he also finished the season having put up career worsts in several areas. In fact, Coleman’s eight touchdowns allowed in coverage for 2019 was more than every season of his career previously combined. He also allowed career highs in targets, receptions, and yardage allowed.

Despite those poor stats, Coleman flashed year round and at points was simply brilliant. He forced three fumbles on the season, and while he looked like a natural using the ‘peanut punch,’ it’s worth noting that he had only forced one his entire career prior to this season. It’s a new weapon to his arsenal, and it looked like he’s been doing it forever.

Drafted in the fifth round, many thought very highly of former Penn State standout Amani Oruwariye. He spent most of the year inactive or sitting on the sidelines in large part due to an injury that still needed healing. Once in, he flashed all of the traits that had many calling him a possible first rounder, finishing the season with the highest grade for any Lions corner per PFF and hauling in two impressive interceptions despite only playing just over 200 snaps on the year. The future looks bright, but there’s reason for concern as well. He allowed over 80 percent of his targets to be completed and ceded three touchdowns, showing an extreme level of variance to his play.

Every other corner, including Darius Slay, graded out below average on the year according to Pro Football Focus. Slay did allow only around 58 percent of his targets to be completed and only three touchdowns all year, tying a career low. It was another Pro Bowl campaign for Slay, and he’s maintained a desire to play for Detroit in 2020 and beyond, but the trade rumblings aren’t going away any time soon.

The Lions will need to look at cornerbacks both in free agency and the draft regardless of what decision is made with Darius Slay, and I’m not sure the overall cost is going to factor into it too much either. If Slay is extended, the team will still need someone opposite him and it’s far too risky to bank entirely on the development of a fifth-round pick. Likewise, if the team decides to move on, likely via trade, the team is going to have to fill that void with someone who can cover with a limited pass rush.

The safeties

The highest-graded Detroit Lions defenders per PFF were pass rusher Trey Flowers and safeties Tracy Walker and Tavon Wilson. When the Lions decided to trade Quandre Diggs for peanuts, he was the lowest-rated safety on the team, even lower than rookie Will Harris. He was a missed tackle machine, missing six tackles in only five games. Diggs would go on to play very well for Seattle, but would miss time due to injury (a not insignificant part of why the Lions were willing to move on).

Tracy Walker was a surprise pick in the 2018 NFL Draft and the Lions staff seemed stoked to bring him aboard. Concerns about his coverage ability and instincts were largely put to rest with his work as a rookie, but as confident as the team was in his abilities as a starter, many fans were skeptical. Despite his promising PFF grade, Walker missed 11 tackles on the year and allowed five touchdowns in coverage (compared to zero for each the previous season). There’s concern with that level of inconsistency, but plenty of promise as he was clearly the best Lions defender in several games this year.

Tavon Wilson would be expected to return in 2020, but despite having the third-highest PFF grade on the defense he is more known for not being bad than he is for being good. Like Walker, Wilson allowed too many passes to be completed (nearly 80 percent in his coverage) and missed too many tackles (10), but he generally played well. If he returns, as many expect, he offers some versatile consistency while the team brings along Will Harris.

Speaking of Harris, that’s where it gets a little more murkier. Harris would finish the year graded lowest of all the Lions safeties (even below Quandre Diggs, though he was above at the time Diggs was traded). Harris would miss six tackles, putting him on the same relative rate as the other two safeties (he had a couple hundred fewer snaps). He also allowed 75 percent of his targets to be completed for three touchdowns, but it’s worth mentioning that despite 461 snaps in coverage he was targeted only 16 times. He also rushed the passer only four times, resulting in a sack and two hurries. There’s plenty of talent there but Harris still hasn’t gotten over his college play where he was basically an unguided missile.

Will it work?

When the Lions drafted Will Harris after having taken Tracy Walker the year before, they were signalling that they intended to rebuild the secondary. The trade of Quandre Diggs solidified that approach so the team just needs to show results Tracy Walker’s play in 2019 is a very good sign that the intention could bear fruit, but the slower development of Will Harris should give a little pause. I wouldn’t expect the Lions to make many moves at safety in 2020 aside from bringing back Tavon Wilson. UDFA rookie C.J. Moore showed some promise as a special teamer so I would expect him to be the fourth man in that unit.

If Wilson doesn’t return, it’s possible the team looks at another free agent or a later round draft pick, but if the team is as dedicated to Will Harris’ development as they were to Tracy Walker, I wouldn’t expect much in terms of resource dedication. Gambling on speed and range should. in theory. give the team more options in terms of what they can call on defense, but that only works if the players that are back there have the instincts and football IQ to remain assignment sound. The firing of Brian Stewart means the team could be looking at a new direction for their secondary which makes the gamble of a player in Will Harris a gamble in development for a new coach. Should Harris show the same level of improvement from college to second year NFL player that Tracy Walker did, the Lions could be set up at safety for a long time.