It shouldn’t have mattered too much that the Union’s starting lineup Saturday in Nashville listed Dániel Gazdag as playing on the left side of the team’s midfield diamond with Jamiro Monteiro at the top, instead of the other way around.

There’s plenty of flexibility built into the formation, and there was the natural expectation that Gazdag and Monteiro would switch places throughout the game so each player could have time on the ball.

But manager Jim Curtin’s decision ended up mattering quite a bit in the 1-0 loss, and he didn’t hide from it afterward.

“I played him a little bit out of position tonight, tilted towards the left,” Curtin said. “Just with the personnel we had available from the start, we thought that was our best option.”

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If that reasoning surprises you, you aren’t alone. In theory, it shouldn’t have been enough to cause a big adjustment, since Leon Flach has done very well at defensive midfield so far. And if the idea was to give Flach better options for passing outlets, since the 20-year-old isn’t as good of a forward-looking distributor yet as José Andrés Martínez, Monteiro could have helped with that.

It turned out that Curtin’s use of from the start had some layers. He revealed that Martínez had some travel headaches returning from the Copa América in Brazil, where he played in all four of Venezuela’s group stage matches. Martínez didn’t return to practice with the Union until Thursday, the day before the team flew to Tennessee.

“We just thought with him being away for so long, to start them would be a little bit unfair to the rest of the guys,” Curtin said.

He didn’t say aloud that it backfired, but he said it with actions by subbing out Gazdag in the 56th minute and sending Martínez in.

Gazdag also admitted that he wasn’t at his best, due to a combination of lack of reps with his new teammates and the last lingering effects of his knee injury. Nor did it help that Nashville played a five-back defense, plus a renowned midfield enforcer in veteran Dax McCarty.

“Of course I want from myself a bit more on [attacking] play, but I’m here since only two weeks,” Gazdag said. “I hope in the next games I will give more and I can give an assist or score goals.”

» READ MORE: Dániel Gazdag missed playing for Hungary at the European Championship because of a knee injury

It won’t take long for him to get another chance, because the Union return to action Thursday at the rival New York Red Bulls (8 p.m., PHL17). That should be a more open game than this one was, not least because the Red Bulls don’t play Nashville’s defensive style.

But Nashville probably deserves more credit than it gets as a second-year team without a big-name attacking star. (Striker Jhonder Cádiz comes closest, another member of Venezuela’s Copa América team.) The club has lost just once in 11 games this season (4-1-6), and now trails the third-place Union (5-3-4) by one point in the Eastern Conference standings.

That back line is a big reason why. All three central defenders stand over 6 feet tall, with veterans Walker Zimmerman and Dave Romney alongside 21-year-old Jack Maher. Zimmerman is a lock to start for the U.S. Gold Cup team this month, and if he does well he could challenge often-underwhelming Tim Ream and Matt Miazga on the World Cup qualifying depth chart.

“They disrupted all of our attacks,” Curtin said. “We couldn’t find the final pass. When you loft balls into the box, they obviously have three centerbacks [including] Walker Zimmerman, who’s probably one of the best in our league at attacking balls in the air.”

Curtin knows his team has faced five-man back lines increasingly often this year, as teams around MLS experiment with that tactical setup. We might see it from the Union at some point, too.

But for now, the focus will be on getting back in the win column Thursday after Nashville snapped the Union’s nine-game unbeaten streak across all competitions.

“We’ll regroup and put out a good performance against Red Bull, I’m confident of that,” Curtin said.

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