Barco, 19, hit the post with a shot in the first half, committed a foul that led to a penalty kick and D.C. United’s second goal in the second half, and passed up two shooting chances -- one in each half -- as Atlanta United’s seven-game unbeaten streak was snapped.

“No, no. no, no,” Martino said. “Sometimes guys have the confidence to finish some of those plays and sometimes they don’t. “

Barco, at $15 million the most expensive transfer into MLS in its history, made his second consecutive start as left midfielder after missing the previous three games because he committed an act of indiscipline.

He earned an assist by taking the corner on Jeff Larentowicz’s game-tying goal in the 39th minute. 

The play was a good example of Barco’s season: though he created a team-high six chances on Sunday, just one of them led to a goal. It was just his second assist in league play this season.

Barco missed a chance to score his fifth goal in the 25th minute when he ran onto a cross by Julian Gressel. Unmarked and with an open goal, Barco’s one-time shot bounced off the post.

Later in the first half, Barco passed up a chance to shoot from a tight angle. The distance and tightness of the shot were similar to the first goal he scored for Atlanta United against Chicago on May 5. He passed up a similar chance from a similar spot deep in the second half with his team trailing 3-1.

Barco has consistently passed up chances to shoot throughout the season. He took the one shot on Sunday.

What seemed to incense Atlanta United’s supporters on social media on Sunday was Barco’s lateness in tracking Paul Arriola, and then fouling him in the penalty box. Though the penalty looked soft, Barco did make contact with his right on Arriola’s right leg. Wayne Rooney converted the penalty to give D.C. United a 2-1 lead in the 52nd minute. Barco failed to track Arriola later in the half. Leandro Gonzalez Pirez came over to cover, receiving a yellow card for his tackle of Arriola.

Barco was replaced by Romario Williams in the 76th minute.

“Especially tonight, I don’t think it’s anything that we have to worry about with him individually,” Martino said. “Tonight was a more collective effort.”

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