José Andrés Martínez’s mix of tenacity, skill, and passion have made him one of the best defensive midfielders in all of MLS over the year-plus he has played in the league.

When the mix of ingredients is off, though, it can be a big problem. And Union fans know all too well that, right now, the mix is off.

Sure, the yellow card that he earned last Tuesday in Atlanta was a bit cheap. But he had to know that a booking would get him suspended for the next game due to card accumulation.

Then came the awful elbow to the head of Valentín Castellanos early in Saturday night’s 2-0 loss to New York City FC. Referee Ismail Elfath rightly sent Martínez off after a quick look at the replay monitor, and the ejection sent the game into a tailspin from which the Union never recovered.

» READ MORE: Union lose, 2-0, to New York City FC and lose José Andrés Martínez to ejection

“A blatant red card and a complete mistake, and José really let his team down,” Union manager Jim Curtin said after the game — a rare public criticism of an individual player.

There was to be “a firm and hard conversation” on Sunday as the rest of the team prepares for Tuesday’s Champions League home game against Atlanta (8 p.m., FS1 and TUDN).

“It’s necessary,” Curtin said. “He’s a great kid, he wears his heart on his sleeve, he’s passionate and he wants to win. But there is a balance between being professional [and] being smart.”

Captain and fellow midfielder Alejandro Bedoya was just as annoyed.

“We need a wake-up call for everybody, and that includes José, who got the red card,” he said. “He plays on the border sometimes, and he’s just got to be smarter. That’s unacceptable.”

Curtin signaled that Leon Flach will start at the defensive midfield spot while Martínez is out, both by words and by deeds on Saturday. Flach went into the role when he came in as a late-game sub Saturday night, and Curtin said that he wanted the 20-year-old to get “a little bit of time at the No. 6 by himself.”

Now the question is for how long Martínez will be out. He’s officially suspended for Tuesday’s game and Saturday’s regular-season contest at the Chicago Fire (1 p.m., 6ABC), but it will surprise no one if MLS benches him for additional time.

Then he will have to face up to another big challenge: being a marked man by referees.

“He’s a guy that I can tell you every referee knows is right on that edge … and is gonna ref him differently,” Curtin said. “It was out of line by José, and, we’ll have to try to improve his behavior on the field. Because we’re not the same team without him, to be honest, and the red cards and suspensions are starting to add up to where it’s detrimental to the group.”

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