What’s difficult about playing 10 vs. 11?

Montreal Impact’s Laurent Ciman, right, challenges Atlanta United’s Hector Villalba during first half of an MLS soccer game in Montreal, Saturday, April 15, 2017. (Graham Hughes/The Canadian Press via AP)

Montreal Impact’s Laurent Ciman, right, challenges Atlanta United’s Hector Villalba during first half of an MLS soccer game in Montreal, Saturday, April 15, 2017. (Graham Hughes/The Canadian Press via AP)

Two on one. The advantages are obvious.

Four on three. The advantages are also obvious.

But as the numbers get bigger, the advantages in soccer may not be as clear.

When it comes to 11 on 10, the numerical disadvantage Atlanta United has found itself in during three of its six games this season, many things can be affected when a team loses a player to a red card or injury. Issues range from tactics to fitness.

“When you are down to 10 men, obviously the other team has an advantage in some area of the field,” Atlanta United midfielder Carlos Carmona said.

Atlanta United next plays on Saturday at Real Salt Lake.

Though the red card given to Leandro Gonzalez Pirez in last week’s 2-1 loss at Montreal was rescinded on Wednesday, it was too late to help the team play a man down for more than 45 minutes.

The team held on until the final few minutes when Montreal scored the game-winner after peppering Alec Kann’s goal with 22 shots, including 13 in the second half. The loss dropped Atlanta United to 0-2-1 when one of its players has received a red card. It is 2-0-1 in games in which it has finished with 11 players. MLS teams that have had a player sent off are 0-13-4 this season.

Dating back to 2015, teams that have had a man sent off have a .298 winning percentage over 176 games.

“It was tough,” captain Michael Parkhurst said. “We did enough in the game to come out of there with something. To lose the way we did was a very fortunate goal on their part at the end. We come out with heads held high. We put up a good fight.”

Practicing playing 11 on 10 isn’t something Atlanta United has worked on in training. Defender Mark Bloom said manager Gerardo Martino praised the team after the loss.

“Yeah, it’s something maybe we are a too familiar with, but he said as we go on, we will work on it more,” Bloom said.

The team’s first two red cards forced Atlanta United to play with 10 men for a just a few minutes in 2-1 loss to New York Red Bulls and then for 15 minutes in the 2-2 draw at Toronto. All of the opponents’ goals in those games were scored before Atlanta United was reduced to 10 men.

If there was an advantage to losing Pirez so early in the game last Saturday, it gave Martino the chance to go over adjusted tactics with the players at halftime. The team sat back and tried to absorb Montreal’s pressure. Sometimes there were as many as nine Atlanta United players in or near its own penalty box.

Montreal tried to spread out Atlanta United, resulting in four corner kicks in the second half and dominant possession time (68.5 percent).

“I think we played really well with 10 men against Montreal,” Carmona said. “I think we showed we could fight, even a man down.”

When a team loses a player in the second half, trying to change man-marking roles and responsibilities for spaces on the field can become very difficult.

“For most part, it messes up your whole formation,” Bloom said. “With 11 men on the field, everybody knows who their man is and where they are supposed to be on the tactical side of it.

“When you go down a man, everybody is scrambling to figure out where they are supposed to be, who they are supposed to cover. So I think there’s a little bit of a delay in the shift to cover everybody. Those small delays at this level create big gaps, so that’s pretty hard to handle.”

And as the players expend more energy trying to cover more space, fatigue becomes an issue. If Atlanta United had all 11 men, someone might have either blocked the shot or been marking Anthony Jackson-Hamel on his game-winning deflected shot.

But Jackson-Hamel did find space in the middle of the defense and his goal came near the end of the game after Atlanta United had competed for more than 45 minutes a man down.

“You can have all the tactics in the world, but if you are tired it all goes out the window,” Bloom said.