The teenagers brought energy and personality, and the newly acquired forward offered a fresh dimension to D.C. United’s limp attack. But when the final whistle sounded Sunday evening at Audi Field, United trudged out of a quiet stadium with a familiar feeling.

It was another scoreless performance, another mix-and-match lineup amid injury absences and ultimately another defeat, 2-0 to the New England Revolution.

United (2-7-5) played well enough for a draw, which, during these dark days, is a small victory. Alas, Gustavo Bou and Adam Buksa scored in the last few minutes as the Revolution (5-3-6) dropped D.C.'s record to 1-5-3 since MLS resumed in-market matches last month.

United has failed to score in four of its past five matches and, after a mildly promising first half Sunday, faded in the last 30 minutes.

“They were knocking at the door, let’s be honest, in the second half,” United Coach Ben Olsen said of the Revolution. Olsen cited New England’s superior “legs and lungs. They had more in the second half, and we started to run out of gas.”

United performed better than Wednesday, when a 1-0 defeat at Nashville prompted Olsen’s furious comments about his starters.

“It was a good response from a work-rate [standpoint], and everyone gave everything they had,” he said Sunday. “That is all I can ask right now of this group.”

The outcome spoiled the debut of forward Yordy Reyna, who was acquired last weekend from Vancouver. Midfielder Moses Nyeman, 16, made his first regular season start, and winger Griffin Yow, 18, got his second.

Julian Gressel, a major preseason acquisition, was dropped from the lineup. He had been the only player to start every match, but his contributions have fallen short of expectations.

Yow, from Clifton, Va., scored a sensational equalizer last weekend in the final moments of a 2-2 draw against Toronto FC. Nyeman, from Riverdale Park, Md., replaced Russell Canouse, who served a red-card suspension.

The starting assignment “was really good experience for both of them,” Olsen said.

Nyeman and Yow rose through United’s academy together and have a sense of each other’s strengths and tendencies. In the 16th minute, they tried to connect, but Nyeman’s through ball was a little ahead of his teammate.

Kevin Paredes, a 17-year-old winger from South Riding, Va., probably would have started as well, but he missed his second consecutive game with a hamstring ailment.

Injuries continued to limit Olsen’s options: Six regulars were sidelined.

United was lively and engaged throughout the first half, a notable improvement after the Nashville dud. It was a good starting point, but those traits did not compensate for shortcomings in the attack. The buildup and commitment were better, but Revolution goalkeeper Matt Turner was not tested.

“We had a few chances that once again we have to do better with,” Olsen said. “We are never a team that puts up 10 to 12 shots; we haven’t been that for a few years. The times we’ve been successful are when we are efficient.”

Early in the second half, both teams were poised to crack the deadlock. United’s Ola Kamara prepared to pounce on a deflection in the box, but defender Andrew Farrell intervened at the last moment.

New England’s Teal Bunbury sent a glancing header over the crossbar, then missed a golden chance from 10 yards.

Midway through the half, Olsen turned to his bench, including Gressel, for an attacking boost. Opportunities remained scarce: a hopeful long ball, a soft effort in the box, a bid from distance.

The Revolution capitalized in the waning moments. Bou found a pocket near the top of the box. Cristian Penilla crossed from the right side. Without anyone applying immediate pressure, Bou settled the ball and tagged a low, 16-yard shot past goalkeeper Bill Hamid.

With United pressed forward, the Revolution doubled its lead on a 90th-minute counterattack when Penilla set up Buksa for a chip over the advancing Hamid.

“Of course we are disappointed, because we needed three points,” defender Frédéric Brillant said. “For me, it is unacceptable to be here right now in the last position in this conference with the team we have, with the quality we have. It’s unacceptable.”

Notes: In a scary moment late in the first half, the match was stopped for several minutes after Reyna’s trailing foot caught Matt Polster on the side of the head as the Revolution midfielder attempted a slide tackle. Polster was helped off the field and evaluated for a possible concussion. …

United will host Atlanta (4-8-2) on Saturday.

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