As the adage goes, defense wins championships. Sure, the fearsome foursome of Tammy Abraham, Paulo Dybala, Lorenzo Pellegrini, and Nicolo Zaniolo already have the pundits purring and will no doubt dominate the headlines over the course of the season. Still, it'll be the defense that will go a long way in helping Roma achieve its objectives for the season.

With Jose Mourinho likely to continue with last season's 3-4-1-2 formation—as evidenced by how Roma have lined up in the various preseason friendlies the team has played—and with only four center-backs currently on the roster, the pressure will be on to keep these players healthy and firing on all cylinders throughout a long season. Oh, and don't forget there's a World Cup in the mix as well.

It remains to be seen whether the club will bring in some reinforcements for the position before the window closes, but in the meantime, let's take a look at the four men tasked with holding down the center-back position.

The Centre-Backs

• Chris Smalling
• Gianluca Mancini
• Roger Ibañez
• Marash Kumbulla

Key Player: Chris Smalling

Photo by Fabio Rossi/AS Roma via Getty Images

Was there ever any doubt that Smalldini would be your key player here? While many doubted him when he first arrived, given how his Manchester United experience ended, Chris Smalling has been nothing short of sensational during his time with Roma, as evidenced by the moniker bestowed upon him by Romanisti.

Arriving at the club on loan ahead of the 2019-2020 season, Smalling quickly endeared himself to the Roma faithful, putting in shutdown performance after shutdown performance en route to becoming one of the premier center-backs in Serie A for the season. Off the strength of his performances and his clear desire to stay at the club, it was always going to be a matter of when, not if, the move would be made permanent.

Unfortunately, Chris' second season didn't go quite to plan. Between protracted negotiations with Manchester United that put into question whether Smalling would even return and an injury-riddled campaign, it was a season to forget for the Englishman.

Fortunately for all parties involved, Smalling found his health and his form last season under Mourinho, even putting to bed the concerns that he wouldn't be at his best in a three-man defense, shining once again and further cementing his role as leader of the defense.

With hype at an all-time high going into the season following the arrival of Dybala and the impending arrival of Gini Wijnaldum, the defense will have to do its part—with a large amount of that relying on the form and health of Smalldini.

Player Under Pressure: Marash Kumbulla

Photo by Fabio Rossi/AS Roma via Getty Images

Often the odd man out in the starting lineup from Roma's center-back quartet, Marash Kumbulla is certainly under the most pressure this season. Practically the lone survivor from Mourinho's post-Bodø purge, Kumbulla found his way out of Mourinho's doghouse the same way Bruce Wayne clawed his way out of The Pit in The Dark Knight Rises.

As we've seen with the other casualties from that loss, The Special One has been firm in his reluctance to utilize those players again, so it's a testament to Kumbulla's talent and ability that he was able to overcome that situation.

The pressure is absolutely on for the Albanian, as a poor season will almost assuredly end his time with Roma, particularly given his links away from the club this summer.

With only four center-backs on the roster and plenty of minutes to go around, this season should be a chance for Marash, Captain of Tirana, to show his quality.

The X-Factor: Roger Ibañez

Photo by Fabio Rossi/AS Roma via Getty Images

Once rumored to be on the radar of both Real Madrid and Barcelona, and named alongside Zaniolo as the players most likely to fetch Roma a hefty transfer fee should either be sold, Roger has the potential to truly catapult Roma's defense from good to great. To do so will require Ibañez to cut out the mistakes and produce consistent performances as Smalling currently does, but the talent is clearly there—it's just a matter of the player taking that next leap forward.

If any manager can help assist in Roger's development, you'd wager on Mourinho to expedite the process.

A Year From Now, We'll Say...

Assuming Roma doesn't get any reinforcements at the position by the end of the summer transfer window, I think we'll look back and see that outcome as a wasted opportunity. I assume if Roma doesn't bring a center-back in this mercato that they'll bring one in come the winter window, but one significant injury early on in the campaign could severely risk the Giallorossi's goals for this season.