The Indianapolis Colts' current roster is way ahead of schedule and after a rough start in the 2018 season, they rebounded in a big way. Frank Reich's first season as a head coach was fantastic and quarterback Andrew Luck returned to his elite form. The offense fired on all cylinders with a top offensive line unit leading the way.

The team saw playmakers on offense emerge last season such as tight end Eric Ebron and running back Marlon Mack.

There is not enough praise that could do the offense justice, but there is some work to be done on defense ahead of the 2019 season. While a clear leader on defense has emerged after linebacker Darius Leonard's shockingly impressive rookie season, there is definite room for improvement elsewhere. The defensive front line was abysmal this past season and while the unit's secondary was surprisingly good there it wouldn't hurt to add more talent to ensure their legitimacy moving forward.

Here are three areas the Colts must improve on in order to become Super Bowl contenders in 2019.

3. Stopping the run

The Colts' run defense was nothing to write home about, but there are some pieces to build around.

Defensive tackle Denico Autry and defensive end Jabaal Sheard are a fantastic foundation for the team to build around and the team could find further help in free agency or through this year's draft. The defense only accounted for 38 sacks in 2018, so needless to say there is plenty of room for improvement. A solid defensive front could put the Colts over the edge in regards to making a Super Bowl run a very realistic possibility in 2019.

Perhaps turning to the draft would be the team's best bet in adding a player capable of providing some solid run stopping capability. Florida State's Brian Burns and Mississippi State's Jeffery Simmons are possible candidates. If the Colts plan to find help without searching through draft prospects, a trade for Seattle Seahawks defensive end Frank Clark is a legitimate possibility and could be a game-changing move for the Colts.

2. Improve upon the run game

The Colts averaged 107.4 rushing yards a game throughout the 2018 season, which ranked 20th amongst the rest of the league. While players like Marlon Mack and Nyheim Hines provided glimpses of a solid run game at times, it became increasingly clear why the team was so pass heavy this past season. The Colts either need to take a closer look at who is left in free agency or commit to Mack considering he showed fantastic playmaking ability last season.

Mack nearly averaged 4.7 yards per carry and played in 12 games in 2018, in which he ran for 908 yards as well as nine touchdowns. The Colts have a solid running back, but they need to make developing him into a workhorse running back a priority ahead of 2019.

Mack is entering his third season and it's likely he could become one of the more efficient backs in the league with a full season under his belt.

1. Strengthen the secondary 

The secondary was actually the unit's most solid layer of their defense in 2018, but why not make that unit even better ahead of the 2019 season. While retaining talented cornerback Pierre Desir, the Colts need a player to complement him on the other side of the field. Some possible candidates in playing alongside Desir are Georgia's Deandre Baker and LSU's Greedy Williams, but Indianapolis may look elsewhere pending on how next month's draft goes.

There is some fantastic talent in this season's draft, so the team will need to do their due diligence in drafting the perfect fit for their secondary to play alongside players like Malik Hooker, Clayton Geathers, Quincy Wilson, and Desir.