How could Atlanta United use a three-man backline?

Portland's Sebastian Blanco, center, tries to corral the ball as Atlanata's Leandro Gonz'lez Pirez (5) defends as the Portland Timbers hosted Atlanta United FC in a MLS match at in Portland, Ore., Sunday, May 14, 2017.  (Sean Meagher/The Oregonian via AP)

Credit: Sean Meagher

Credit: Sean Meagher

Portland's Sebastian Blanco, center, tries to corral the ball as Atlanata's Leandro Gonz'lez Pirez (5) defends as the Portland Timbers hosted Atlanta United FC in a MLS match at in Portland, Ore., Sunday, May 14, 2017. (Sean Meagher/The Oregonian via AP)

Atlanta United manager Gerardo Martino on Monday said the team will spend part of its training camp working on a three-man backline.

The formation, which typically includes three central defenders, five midfielders and two strikers, was used by Atlanta United a few times last season, notably against Orlando City.

It’s a departure from the 4-3-3, or 4-2-3-1, that the team used more than 90 percent of the time last season in securing the fourth seed in the MLS Eastern Conference playoffs and scoring the second-most goals in the league (70).

The change would seem to be a way to accommodate the wealth of midfield talent the team has with new faces Darlington Nagbe and Ezequiel Barco joining Carlos Carmona, Jeff Larentowicz, Miguel Almiron and Hector Villalba, among others.

But it introduces new questions: Notably, who would be the right wingback? Or would there even be a right wingback?

If the team uses a 3-5-2, the back three seem likely to be:

Michael Parkhurst, Leandro Gonzalez Pirez and Franco Escobar.

The five midfielders, from wide left to wide right, would likely be: Greg Garza, Barco, Carmona, Nagbe and Villalba. The two strikers would be Almiron and Josef Martinez. Almiron could play underneath Martinez and ahead of Carmona, who would likely be a deeper midfielder.

The plus of that personnel is there a lot of fire power going forward.

The minus is either Nagbe or Villalba would have to be the ones to get up and down that right side. That was a periodic issue for Villalba last season. Nagbe’s defense is unknown.

It also raises the question of where would Julian Gressel, the reigning MLS Rookie of the Year, and Larentowicz play?

The answer may be they would come in as subs when Atlanta United has leads to add some teeth to the midfield and shore up the defense.

Larentowicz can play as a centerback, which would allow Martino to shift the 3-5-2 to the 4-2-3-1. Gressel can play anywhere except as a centerback. He played at least five different positions last season.

Larentowicz said it’s not difficult to switch formations from game to game, or even within games. The team would sometimes make the shift going the other way, 4-2-3-1 to a 3-5-2, during games last season.

The difference in a three-man backline and four-man backline is the team is either taking away or adding something to the attack, depending upon which formation is used.

A three-man backline may seem scary to some Atlanta United fans. The team was sometimes susceptible to counter-attacks last season, and that’s when they were using a four-man backline. Of course, because Martino encourages the outside fullbacks to play as far up the field as possible, that four-man backline was four in name only. It typically was just Parkhurst and Gonzalez Pirez shielded by Carmona and Larentowicz.

Or, Martino could simply continue to use the 4-2-3-1 he used last year.

In that formation, the back line would likely be: Garza, Parkhurst, Gonzalez Pirez and Escobar. The two defensive midfielders would be Carmona and Nagbe. The three across the midfield would be Barco, Almiron and Villalba. The striker would be Martinez.

Martino said Monday that he’s not sure how he can fit all of the midfield talent into a formation. He joked that the team may ask the league if they can field 12 or 13 players.