CLEVELAND — The 2019 NFL season is almost here.

And optimism in Cleveland isn't hard to find.

Following what was their best season since 2007, the emergence of Baker Mayfield, and the offseason acquisition of Odell Beckham Jr., the Browns enter their upcoming campaign as one of the NFL's hottest teams. According to multiple sportsbooks, Cleveland is favored to win the AFC North and has received the most bets to win the Super Bowl entering the new season.

But despite the preseason hype the Browns are currently enjoying, nothing in the NFL is guaranteed. And while Cleveland may lay claim to some of of the NFL's top talent, the Browns could still find themselves facing several hurdles in the upcoming season.

With that in mind, here's a look at the three biggest problems that could potentially derail the most highly anticipated Browns season in recent memory:

Offensive line issues

For all the additions the Browns made to their roster this offseason, at least one unit seems to have suffered a setback. Cleveland enters the 2019 season with a weakened offensive line that possesses the potential to serve as the team's Achille's heel in the months to come.

As a part of the deal to acquire Beckham and defensive end Olivier Vernon, the Browns sent starting right guard Kevin Zeitler to the New York Giants. Entering Week 1, journeyman Eric Kush is slated to fill that void, although it may only be a matter of time until recently acquired Wyatt Teller takes over.

Elsewhere inside, Cleveland is strong with center JC Tretter and Pro Bowl left guard Joel Bitonio returning to their respective roles. Greg Robinson and Chris Hubbard also return as the Browns' offensive tackles, although both players have been inconsistent -- at best -- for the better part of their careers.

Perhaps most alarmingly, Cleveland's offensive line depth leaves plenty to be desired. The offseason release of Desmond Harrison leaves the Browns dangerously thin at tackles, while former second-round pick Austin Corbett appeared to be in danger of keeping his roster spot after originally entering training camp as the starting right guard.

Cleveland's offensive line doesn't need to be great. It does, however, need to be good enough in order for all of the talent elsewhere on the Browns offense to have a chance to shine.

JC Tretter Cleveland Browns training camp August 10, 2019
Cleveland Browns center JC Tretter prepares to snap the ball during a drill at training camp practice Saturday, August 10, 2019.
Matt Florjancic

Defensive depth

On paper, the Browns lay claim to one of the more talented starting defenses in the NFL. Defensive end Myles Garrett is already a star, Vernon and Denzel Ward are each coming off Pro Bowl seasons of their own and Larry Ogunjobi, Sheldon Richardson, Joe Schobert, Christian Kirksey and Damarious Randall are all experienced players who have proven capable of playing at a high level.

But given the realities of an NFL season, starting lineups are always subject to change.

And if -- and when -- the Browns suffer a significant injury on defense this season, their depth will be put to the test. Cleveland is just a play away from being forced to put inexperienced players on the field at all levels of its defense, including on its defensive line, linebacking corps and secondary.

While Sione Takitaki, Mack Wilson and Greedy Williams have yet to play an official NFL snap, all three rookies possess high upside and could factor prominently into Cleveland's future. But in the short-term, the Browns are going to need them to not only contribute on special teams, but also potentially provide depth on a defense that may otherwise be lacking.

RELATED: Cleveland Browns’ Color Rush uniforms will be team’s primary look for 2019 season

RELATED: Will special teams inexperience hurt the 2019 Cleveland Browns? -- Bud Shaw's You Said It

RELATED: Cleveland Browns unveil unofficial depth chart for Week 1 of 2019 season

Greedy Williams Cleveland Browns Training Camp
Cleveland Browns defensive back Greedy Williams (26) blocks during a special-teams drill at training camp in Berea on Saturday, July 27, 2019.
Matt Florjancic

Underwhelming understudies

The thing about having a franchise quarterback -- as the Browns appear to have in Mayfield -- is you need him to stay healthy in order to live up to the expectations.

Obviously, that could be said for any team, but for the Browns, it rings especially true. Whereas other franchises may be able to survive their star signal-caller missing a game or two, any game action missed by Mayfield could prove significant for Cleveland, considering the team's backup quarterback situation.

While head coach Freddie Kitchens insists he has faith in Drew Stanton, it's worth noting the 35-year-old hasn't appeared in a regular-season NFL game since 2017 and has only attempted more than 100 passes in three seasons since being drafted in 2018. Garrett Gilbert, meanwhile, has appeared in just one NFL game with the 28-year-old's most significant professional football experience coming in the already defunct AAF.

If the Browns are going to have any chance of breaking their 17-year playoff drought, they're going to need Mayfield to take as many snaps as possible. Considering the alternatives, any time missed could prove crucial in determining whether or not Cleveland's highly anticipated 2019 campaign lives up to the hype.