It took D.C. United all of three minutes Sunday to understand that the dismissal of longtime coach Ben Olsen would be no miracle cure for the team’s ills.

After United surrendered a goal to the Chicago Fire in the opening moments of Chad Ashton’s debut as interim coach, the visitors conceded again just before halftime in a 2-1 loss at Soldier Field. Although a Chicago own goal gave United a second-half jolt, it wasn’t enough to snap what is now a five-game losing streak or lift Ashton’s team out of last place with six games remaining.

“You know you have to start and end halves, and winning teams do that well, and teams that are struggling don’t do that well,” Ashton said. “There’s just no moral victories in this. You’ve got to find a way to get results.”

C.J. Sapong and Boris Sekulic scored for the Fire (5-8-4), which moved into postseason position with the victory. United (2-10-5) sits seven points out of a spot in the expanded, 10-team Eastern Conference playoff field.

The match came three days after United dismissed Olsen, ending the longest coaching stint in team history and marking the departure of a club icon who has been associated with D.C. as a player or coach for 23 of the franchise’s 25 seasons.

Ashton marked the start of his tenure by implementing a high press that at times rattled the Fire, halting Chicago attacks in their infancy and creating opportunities for United on the counter. And a D.C. team that routinely loses the possession battle had 52 percent of the ball. But Ashton’s squad was plagued by many of the same issues that contributed to Olsen’s departure, including early goals conceded, lackluster set-piece defending and errant finishing.

“We are in the bottom of the standings. Nothing is going well, so it’s tough for everybody,” defender Frédéric Brillant said. “We had the ball today, so it’s much better. . . . It’s coming. We have to stay positive.”

With his first lineup, Ashton shifted from the lone-striker formations Olsen had favored of late and deployed Erik Sorga and Gelmin Rivas as dual forwards in a 4-4-2 alignment. It was their second and fourth starts of the season, respectively, while leading scorer Ola Kamara (14 starts, three goals) shifted to the bench.

Chicago moved quickly to sour the occasion. Rivas committed a sloppy foul in his own end, Alvaro Medran whipped in the subsequent free kick, and Sapong (Forest Park High, James Madison University) stabbed home a shot from close range.

“It’s just absolutely brutal,” Ashton said. “You come into a game, you’re fired up, and then you’re in a hole immediately.”

The Fire nearly doubled the lead a minute later, when Medran rattled the post with a 25-yard blast. But United soon stabilized.

D.C. came closest to equalizing in the 16th minute, when Chicago goalkeeper Bobby Shuttleworth struggled to corral Rivas’s header off a Julian Gressel cross. Yamil Asad slipped in Sorga for another promising opportunity in the 32nd minute, but the Estonian drilled his shot wide of the near post.

The Fire again took advantage of a set piece to double its advantage in first-half stoppage time. Asad lost track of Sekulic on a Medran corner kick, and the Chicago defender guided a floating header past United goalkeeper Bill Hamid.

“We had the ball. We had some chances,” Brillant said. “And we concede the second goal.”

United halved the deficit in the 56th minute. Some clever combination play allowed Júnior Moreno to free Joseph Mora down the flank, and the left back rifled a shot toward the far post. Although the deflected effort was off the mark, Chicago defender Jonathan Bornstein fumbled an attempted clearance and prodded the ball into his own net.

Ashton promptly freshened United’s forward corps with Kamara and Peruvian attacker Edison Flores, who returned following a nine-match absence because of a facial fracture and concussion suffered in late August.

In the 68th minute, Kamara launched a 15-yard shot off the crossbar. Three minutes later, Shuttleworth parried away Flores’s blast and Asad’s long-range bid in quick succession.

But an equalizer never arrived for United, which dropped to 1-8-3 since MLS resumed home-market matches in late August.

“We did a lot of the things that we talked about over the past few days,” Ashton said. “We did a better job with the ball. We did a better job creating chances, but we gave up two set-piece goals that, for me, are just soft. We’ve got to start the game better. We’ve got to not dig ourselves the hole.”

Notes: Midfielder Moses Nyeman was left off the game-day roster because of a minor injury. He is expected to be available for Wednesday’s match against the Philadelphia Union at Audi Field. … The game marked United’s first trip to Soldier Field since October 2005. The Fire played at a soccer-specific stadium in Bridgeview, Ill., from 2006 through 2019 before the club reached a deal to exit its lease at the sparsely attended suburban venue.

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