08/03/2013 09:51 EDT | Updated 10/03/2013 05:12 EDT

Impact fall 3-1 to United, miss chance to secure top spot in Eastern Conference

WASHINGTON - It is difficult to know exactly what to expect from the Montreal Impact these days.

On Saturday night, the team that beat Eastern Conference powerhouse Sporting Kansas City a week ago was nowhere in sight against the worst team in MLS.

Substitute Conor Doyle chipped home his first career goal in the 68th minute to break a tie score and eventually lift D.C. United to a 3-1 victory over the Impact at RFK Stadium.

A chance to take sole possession of first place in the conference, against a team that had scored fewer goals (10) all season than Montreal's leading scorer, Marco Di Vaio (11), escaped the Impact. That result could prove costly over the season's final 13 games.

"Our reaction from their second goal was poor," Di Vaio said. "There's no other way to describe it. I think we always need to be honest with ourselves when things don't go well. The way that we reacted we didn't deserve to get back into the game. It was like we were hoping."

United, which entered the game with just 10 standings points, had scored two goals in a game just once all season and had yet to score three. It took a strong effort from keeper Troy Perkins to keep D.C. from more. He faced nine shots on target while his teammates managed just five.

Montreal, with 21 games played, would have leapfrogged into first place in the standings after Sporting KC's 3-2 loss to the New York Red Bulls on Saturday. Instead the Impact remain in third place with a 10-6-5 record and 35 points. Over the last nine games Montreal's record is a mediocre 2-4-3.

The Impact shook off a shaky start when defender Jeb Brovsky recorded his own first career goal early in the second half to level the game. That tally in the 52nd minute, a clinical finish on a give-and-go with teammate Davy Arnaud, beat a diving Joe Willis in net. The right-footed shot nestled in the left corner and gave Montreal needed life.

"But I would have traded that goal for three points," Brovsky said. "Hell, I would have traded it for one point. I'm happy that I got my first goal, but that goal didn't get us any closer to the playoffs."

The Impact's effort faltered again. With 22 minutes to play before injury time, United's James Riley got off a cross into the box. Doyle was ineffectively marked by Montreal defender Hassoun Camara and he used his right foot to deflect the ball past Perkins for the eventual game-winner.

"The way the second goal comes is too easy," said Perkins, who was playing against his former team. "It's an easy ball in and the guy is by himself. That's happened to us too many times now. And the reaction was not good — as though too many guys quit."

Luis Silva had scored the game's first goal in the 19th minute. A cross from United's Nick DeLeon deflected off a Montreal player and eventually landed at Silva's feet. Impact defender Dennis Iapichino had his back to Silva at the top of the box and struggled to stay in front.

Instead, he effectively created a screen. Silva's shot flashed past a diving Perkins and smacked off the left post and in.

With Montreal desperately pushing forward to tie the game late, D.C. countered with a 2-on-0 against a helpless Perkins. Jared Jeffrey sent the crowd of 12,354 home happy when he tapped home a pass from Doyle. Several dozen Impact supporters in the end zone seats could only groan as rain poured down upon them.

"I don't care who you're playing," Di Vaio said. "You have to have 11 guys who are up for it and ready to grind out a result."