Tennessee Titans quarterback Marcus Mariota's NFL career has not really gone as planned.

After a couple of impressive years to begin his time with the Titans in 2015 and 2016, Mariota has been on a downward spiral ever since, putting forth incredibly disappointing performances the last two seasons to the point where some have questioned his future under center.

Of course, injury issues have not helped the matter, but Mariota threw just 24 touchdown passes combined in 2017 and 2018 while serving up 23 interceptions. Not exactly the best ratio.

The thing as, the Titans are a pretty solid team as a whole and came within one game of making the playoffs this past season.

So, here are some early goals for Mariota to help propel Tennessee into the postseason in 2019.

3. Stay Healthy

Obviously, this is somewhat out of Mariota's control, but he can at least hope for the best in terms of health, right?

In 2017, Mariota had hamstring issues that limited him for a good chunk of the year. He only missed one game, but even when he was on the field, you could tell he wasn't right, and he ended up finishing with 13 touchdowns and 15 picks.

Then, this past season, neck and elbow issues hampered the signal-caller, causing him to miss a pair of contests. Overall, he threw for 2,528 yards, 11 touchdowns, and eight interceptions, very underwhelming numbers for a former No. 2 overall pick.

While we can't solely blame injuries for Mariota's struggles, they have certainly played a role, as he looked pretty solid with good health over his first couple of seasons.

If the 25-year-old can stay healthy in 2019, he should have a better year.

2. Throw for 3,500 Yards

I'm not sure Mariota will ever be able to throw for 4,000 yards. Maybe he will one day, but as of now, he is yet to even eclipse 3,500, which should be a goal of his heading into 2019.

After all, Mariota did throw for 4,454 yards during his final year at Oregon, and while he does not have the arm strength of a Daunte Culpepper, it's not like he has a noodle arm.

In this modern era of football, it's tough to win if your quarterback isn't piling up yards. Russell Wilson is probably the exception, but even he threw for over 4,000 yards in back-to-back years in 2015 and 2016.

Marcus Mariota, Titans

Now, to be fair to Mariota, Tennessee has not asked him to throw the ball all that much, but his lifetime average of 7.5 yards per attempt stands to be better.

With wide receiver Corey Davis entering a potential breakout season and Adam Humphries now in tow, look for the Titans to give Mariota a bigger opportunity in 2019.

1. Improve the Touchdown-to-Interception Ratio

No matter how you spin it, essentially posting a 1:1 touchdown-to-interception ratio over the span of two years is hideous.

Yes, Mariota has had some injury issues. Yes, the Titans don't ask for much of him. But, again, 24 touchdowns and 23 interceptions in 2017 and 2018 is inexcusable any way you slice it.

No one is asking Mariota to go out there and be Tom Brady; he just needs to be the best version of himself, and the best version of Marcus Mariota thus far came in 2016 when he threw 26 touchdowns and just nine picks.

There is no reason why he can't do that again, and there is certainly no reason why he can't, at the very least, throw twice as many touchdowns as interceptions.

If Mariota does that, the Titans will have a good shot of going to the playoffs.