The Houston Dynamo barely sneaked into the playoffs after slumping toward the end of the regular season. Now, they're on the verge of repeating as Eastern Conference champions.

Surprising Houston hosts the opener of the two-leg aggregate conference finals Sunday versus a D.C. United team it has had plenty of success against in recent seasons.

The Dynamo had gone 2-3-4 in their previous nine games before clinching the East's fifth and final playoff spot with a win over Philadelphia on Oct. 20 in their second-to-last game of the regular season. That spotty play down the stretch forced a difficult road for them to defend last season's conference championship.

Houston won 2-1 at fourth-seeded Chicago on Oct. 31 to advance to the semifinals versus top seed Kansas City, taking the first leg 2-0 last Sunday before falling 1-0 on Wednesday but winning the aggregate series.

"We knew when we got the fifth spot we were going to have to earn it," coach Dominic Kinnear said. "We had to roll up our sleeves, put our tin hat on and defend for our life.

"The one thing that really impresses me is that getting to the conference finals was going to be a tough road. We showed a lot of heart."

Will Bruin has scored three of the Dynamo's four playoff goals - he led the team with 12 during the regular season - and assisted on the other by Adam Moffat last Sunday.

Bruin, who has three goals in three games versus D.C. this season, hardly played in last year's postseason as a rookie. Still, Houston ousted Kansas City in the East finals before falling to Los Angeles in the MLS Cup final. The Dynamo haven't won a league title since claiming back-to-back Cups in 2006 and 2007.

They're 6-1-1 in the last eight meetings with United and won the final two matchups this season by a combined 5-0 score. Both of those games were in Houston, where D.C. is 0-7-1 all-time and has lost its last visits.

United, though, are 3-0-2 in their past five road games and are coming off a thrilling victory away from home. After a 1-all draw at D.C. in the first leg of their aggregate semifinal series against New York, United went on the road Thursday to beat the Red Bulls 1-0 on Nick DeLeon's goal in the 88th minute.

Backup goaltender Joe Willis made a crucial stop on a penalty kick in the 73rd. Willis entered after starter Bill Hamid received a red card, and he proceeded to allow the first penalty kick attempt to get through. However, it was ruled New York entered the penalty area too soon, and Willis stopped the second attempt.

"When the chips are down there is a certain spirit about them, it has nothing to do with me," coach Ben Olsen said. "These guys have just come together by themselves. They gelled and they believed and sometimes belief is enough."

United, who haven't reached the MLS Cup final since winning it in 2004, have one less day to prepare for Sunday's first leg due to the rescheduling of its series with New York because of Superstorm Sandy and a snow storm.

"It was always going to be a short turnaround either way," Olsen said. "It's not a lot of time, (Houston has) an extra day but they had a short end earlier, they had two days rest on their first leg. It's evened out - it would be a day game there, it may be a little hot, but I'm not too concerned."