Union edge Mexico’s Atlas, 1-0, in Champions League with late Dániel Gazdag goal

Stylistically, it was probably the Union’s best game of the season. On the scoreboard, though, Tuesday’s Concacaf Champions League home game against Mexico’s Atlas was a narrow 1-0 win, decided by Dániel Gazdag’s late penalty kick. That makes next Wednesday’s game in Guadalajara (10 p.m., FS1, TUDN) an even bigger challenge.

If the Union play in that game with the verve they showed here, it could go well. But they rued taking so long to score while playing with a man advantage for the entire second half, even though Atlas packed it in defensively with a five-man back line and one forward.

The Union knew they had to run up the score before next week’s game in Guadalajara, so manager Jim Curtin ran out an attack-minded lineup: a 4-3-2-1 formation with Joaquín Torres and Gazdag behind Julián Carranza, and Jack McGlynn on the left side of the line of three.

That lineup produced three shots in the first 15 minutes, and there would have been a fourth had Gazdag not been flagged offside — incorrectly — after a tremendous steal and lofted pass by McGlynn.

The biggest chance of the half, though, went to Atlas in the 25th minute. Star forward Julián Quiñones broke behind the Union’s back line, but Damion Lowe chased him down, Andre Blake came off his line, and they both did just enough to stop Quiñones before slamming into each other.

The ball sprung loose and Quiñones got to it, but Lowe blocked Quiñones’ ensuing shot. Jakob Glesnes and Olivier Mbaizo then moved to escort the ball away, and only just did.

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With seconds to go in the first half, Carranza broke in behind and cut left into the 18-yard box, then felt Atlas’ Carlos Robles put a hand on his back. Carranza went down and there was definite contact. Salvadoran referee Hector Martinez let it go, but the video review officials told him to take another look.

Martinez duly went to the monitor, took quite a long look, and stuck with his original call.

But Atlas’ good luck wouldn’t last long. Barely 30 seconds after play resumed, Joaquín Torres sprung Gazdag loose, and Anderson Santamaría shoved him over just outside the 18-yard box. Martinez blew his whistle immediately, and raised his red card before Santamaría was off the ground.

Close-range free kicks are often difficult to pull off, because the space in front of the shooter is compressed. But the Union almost did it with a neat bit of trickery: McGlynn faked a run-up, then Carranza fizzed a low shot just wide right.

Santamaria’s departure took Atlas’ top centerback off the field. Manager Benjamín Mora responded by reinforcing his defense, pulling star striker Julio Furch at halftime and sending in right back José Abella to make a 5-3-1 formation.

Curtin waited a few minutes to see if his starters could break through. As the hour mark approached, Mikael Uhre was summoned, and went in for Torres. That changed the Union’s setup back to its usual 4-4-2.

Uhre’s first big contribution was a shot off the post in the 67th minute. Three minutes later, Glesnes forced Atlas goalkeeper Camilo Vargas to make a flying save of a deflected free kick, and seconds after that Vargas had to make a reflex stop on a McGlynn shot that flew through traffic.

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Curtin upped the ante further in the 72nd by sending in Quinn Sullivan for Mbaizo and moving Alejandro Bedoya to right back. That set the team up in a 4-3-3 with Carranza, Uhre, and Sullivan on the front line.

In the 75th, McGlynn nearly brought the house down with a cut on to his left foot and blast from 18 yards that forced a big save by Vargas.

The clock read 85:54 when José Andrés Martínez lofted a long ball toward Carranza at the edge of the 18-yard box. As the ball fell, Vargas ran off his line and jumped for it, but missed. He didn’t miss Carranza though, and the whistle came fast.

The penalty kick didn’t come until nearly three minutes later, thanks to a commotion that ensued after the foul. During that commotion, Atlas’ young rising star midfielder Brian Lozano got a yellow card that was his second of the tournament, meaning he’ll miss next week’s game due to yellow card accumulation.

Eventually, Gazdag stepped up to the spot, shot low, and though Vargas got a piece of the ball, it snuck in under him.

While so much focus was on the Union’s attack, Curtin made a big decision on the back line, too.

With Kai Wagner sidelined due to a hamstring injury, Nathan Harriel started at left back so Matt Real can be ready for Saturday’s regular-season game at FC Cincinnati (7:30 p.m., Apple TV, paywalled). Harriel played quite well: 37 touches, 23-of-25 passing, three tackles, two recoveries, one interception, and five duels won out of 10 contested.

Harriel didn’t make as many attacking forays as Wagner and Real usually do, but he made a big one in the 30th minute and could have won a penalty kick from it. Robles budged him from behind, but Martinez and the video review crew didn’t think there was enough contact. Replays showed there was a little less than initially thought, but that level of contact has been whistled before.

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