Many expected first-year head coach Mike Vrabel would help turn around the Tennessee Titans defense in 2018.

He has.

After 11 weeks of action this season, the Titans now find themselves with the second best scoring defense in the league, having surrendered just 189 total points and allowing a mere 5.5 yards per play. While generating turnovers hasn't been much of a strength, at least Tennessee is preventing opponents from getting into the end zone.

That said, there are still some major holes and issues on both sides of the ball. Offensively, the Titans have struggled aplenty, particularly through the air, where quarterback Marcus Mariota is leading a passing attack gaining an average of just 5.9 yards per attempt — 26th best in the NFL. Overall, the Titans have mustered just 1,837 pass yards this season, which is third worst entering Week 12.

Yeah, there are some needs needing to be addressed.

The Titans have six total picks in the upcoming 2019 NFL Draft (minus their own selection in Round 6) and are currently slated to pick 17th overall.

On a down note, this year's class isn't particularly deep on offense, where the Titans need a lot of help. But there are plenty of upgrades needed on the defensive side of the ball too, making Vrabel and Co.'s choices interesting, to say the least.

Mike Vrabel, Titans

Let's take a look at the five biggest areas they'll need to address come the draft.

5. Tight End

Losing veteran tight end Delanie Walker to a season-ending ankle injury hurts. He long established a rapport with Marcus Mariota. But Walker will turn 35 years old before the 2019 season begins. And while he's currently signed through 2020, the Titans would be wise to consider finding an eventual replacement.

Twenty-three-year-old tight end Jonnu Smith has been the prime beneficiary of Walker's absence. The problem, however, is Smith has contributed scantly in the passing game. To date, he has a mere 16 receptions for 166 yards and two touchdowns — a far cry from the kind of numbers Walker was expected to put up this season had he stayed healthy.

Even if Walker is able to return fully healthy, Tennessee would benefit from adding another pass-catching tight end.

delanie walker

Keep in mind, offenses boasting two capable tight ends are some of the most difficult to defend. Walker's prowess is still going to be potent, albeit for a short while.

So, if the Titans offense wants to take advantage of Mariota's prime years, grabbing an additional weapon here would go a long way.

4. Offensive Guard

If Marcus Mariota is the Titans' top offensive weapon, it's pretty obvious keeping him upright as much as possible is a good idea.

So far, Tennessee hasn't done this particularly well. The Titans have surrendered 33 sacks on the year, which is tied for fifth most in the NFL. And Football Outsiders has their offensive line ranked dead last in pass protection heading into Week 12.

Veteran right guard Josh Kline has been the primary culprit here, allowing just three of those sacks but leading the team with 15 total quarterback hurries, according to Pro Football Focus. And at 28 years old, he's probably not going to get much better in this department either.

Taylor Lewan

Unlike last year, the 2019 NFL Draft isn't particularly deep at offensive guard. So unless free agency is the route Tennessee takes, spending an early pick in the draft to upgrade Mariota's protection wouldn't be a bad idea.

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3. Running Back

It certainly isn't the biggest offensive problem for Tennessee this season. But to say the Titans' running game has been meeting expectations in 2018 is a pretty big overstatement.

The Titans fully endorsed running back Derrick Henry as their go-to ball carrier this season. Adding veteran pass-catching tailback Dion Lewis during the offseason was intended to give the offense another dynamic out of the backfield too.

The problem, however, is neither back has fully provided the necessary production. Henry is averaging a mere 3.7, while Lewis is even lower at 3.4 yards per attempt. Lewis' receiving numbers are up to par, which is a good thing. But at 28 years old, one has to wonder how long he'll remain a legitimate threat.

Tennessee could use a young, dynamic runner to take the pressure off the passing game and open things up for Titans offensive coordinator Matt LaFleur, who had tremendous success with the Los Angeles Rams and running back Todd Gurley a season ago.

Just imagine if LaFleur had a Gurley-type back in his ranks. OK, most teams would want a player like Gurley.

Still, that doesn't negate the need to upgrade the ground game this offseason.

2. Outside Linebacker

While the Titans defense has done a great job and has exceeded expectations this season, they're still hurting in arguably the most important aspect on this side of the ball: the pass rush.

Entering Week 12, Tennessee's defense has just 23 sacks on the year, which is tied for 23rd and even ranks worse than the Tampa Bay Buccaneers. Remember the Bucs' pass rush from a year ago?

Brian Orakpo, Titans

If there's good news, the Titans are spreading the sack production around a bit. Yet there's also a clear absence of a true pass-rushing outside linebacker. And with veteran backer Brian Orakpo playing the final season of his four-year, $31 million deal, it's about time Tennessee gets both younger and cheaper.

Fortunately for Tennessee, the 2019 NFL Draft is laden with both edge rushers and solid outside linebacker prospects deep into day two.

While one of the top-quality pass-rushers would be ideal, the Titans could still settle for a second-rate option and get some much-needed reinforcement in this department.

No. 1: Wide Receiver

As if tight end needs weren't enough, the Titans still need additional targets for Marcus Mariota. It seems as if that's been a trend for more than a few years now.

Corey Davis

2017 first-round NFL Draft pick Corey Davis is starting to look like a bona fide threat at the position after a disappointing rookie year. That said, he's only sitting at 606 yards on 45 targets with just two touchdowns. Based on that alone, he's looking more like a complementary receiver and not exactly a go-to guy.

Davis' efforts haven't been helped by Mariota's injuries and some inconsistent offensive production. But the Titans would be more than wise to add a tough, physical wideout capable of forcing opponents to scheme their defenses against him.

Unfortunately, there aren't exactly a ton of viable options in this year's draft class. Ole Miss' A.J. Brown might be high on Tennessee's wish list, particularly if the team is comfortable using a first-round pick on him.

At any rate, one would be shocked if the Titans elect not to add some muscle at this position come draft day.