[MLS CUP PLAYOFFS: Houston-D.C. United] The Houston Dynamo took a huge step toward defending its Eastern Conference crown, scoring three unanswered goals from Andre Hainault, Will Bruin and Kofi Sarkodie in the second half to secure a 3-1 win over D.C. United in the first leg of the Eastern Conference final before a a BBVA Compass Stadium record crowd of 22,101.

Houston's superior depth was the difference as reserves played key roles on all three goals, while D.C. United, already shorthanded, lost two starters in the first half with injuries.

But a non-call at the end of the first half that could have given D.C. a man advantage changed the game and was its focus in the postgame discussion.

-- Already without injured star Dwayne De Rosario and goalie Bill Hamid and Andy Najar, both suspended, D.C. United lost Chris Pontius in the 12th minute and Marcelo Saragosa in the 40th minute with injuries. Raphael Augusto, who had not played a game since arriving on loan from Fluminense in July, was brought on for Saragosa. Early in the second half, Argentine Emiliano Dudar, who hadn’t played in more than two months, had to come on in place of center back Brandon McDonald.

-- United, which has never won in nine games in Houston, took a 1-0 lead in the 27th minute when Lionard Pajoy rifled a shot off the far post, and rookie Nick DeLeon put the rebound away.

-- D.C. United screamed for a red card in stoppage time when Hainault took down Raphael Augusto outside the Dynamo penalty area. Not only did referee Ricardo Salazar not show a red card, he didn't not even call a foul.

-- D.C. United assistant Pat Onstad was ejected for arguing the call, and D.C. head coach Ben Olsen confronted Salazar after game. “What do you want me to say? What can I say about it?” Olsen said. “Everybody in the stadium, everybody on our bench, everybody on their bench, everybody at home saw that it’s a red card. It’s a takedown. It’s a red card. I don’t know what to say about it. It’s very, very frustrating.”

-- Houston evened the score in the 51st minute when Hainault scored from close range after a short free kick was played by Brad Davis to Oscar Boniek Garcia, whose pass found the Canadian free at the far post. Hainault was inserted in the starting lineup after Jermaine Taylor was injured in the series with Sporting Kansas City.

-- Giles Barnes, who entered the game for the injured Angus Moffat in the first half, set up the second goal with a strong run in from the left wing and fed Bruin for the go-ahead goal, the Indiana product's fourth in four playoff games.

-- On the third Dynamo goal, Raphael Augusto failed to shut down Luiz Camargo, who was playing in place of Ricardo Clark, and Luiz Camargo fed Sarkodie, who blasted a shot from a tight angle past Joe Willis.

-- The win extended Houston’s home unbeaten streak to 30 games in all competitions, dating to June 18, 2011. The Dynamo are now 8-1-0 all-time in home playoff games, outscoring opponents 18-6.

Second leg: Sunday, Nov. 18, 4 p.m. ET in Washington, D.C.

Nov. 11 in Houston
Houston 3 D.C. United 0. Goals: Hainault (Garcia, Davis) 51, Bruin 68, Sarkodie (Luiz Camargo) 81; DeLeon 27.
Houston -- Hall; Sarkodie, Hainault, Boswell, Ashe; Moffat (Barnes 25), Luiz Camargo, Davis (Creavalle 88); Garcia, Bruin (Ching 88), Kandji.
D.C. United -- Willis; Russell, McDonald (Dudar 56), Jakovic, Korb; DeLeon, Kitchen, Saragosa (Augusto 40), Pontius (Neal 12), Boskovic, Pajoy.
Referee: Ricardo Salazar.
Att.: 22,101.