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D.C. United endured a stretch of 37 games spanning four seasons that turned the home of the four-time MLS Cup champions, RFK Stadium, into a vacation spot for opponents.

This season, D.C. reclaimed its venerable home.

Sunday against the Houston Dynamo in the second leg of the Eastern Conference finals, United will try to complete an amazing turnaround at home, and secure one more match at its old stadium this season - the MLS Cup final.

The challenge is overturning a two-goal deficit from the first leg, a 3-1 win for Houston last week at BBVA Compass Stadium, where the Dynamo were unbeaten all season.

D.C. has just a single blemish at RFK this season, back in early March in the opening game of the MLS season against Sporting Kansas City.

That loss dropped United to just 8-20-9 at RFK over a 37-game span that began late in the 2009 season. After losses in three of its last four home games in 2009, D.C. won just seven of a combined 32 home matches in 2010 and 2011.

"Not good at all," United attacker Chris Pontius said earlier this season.

Since, United has gone unbeaten in 17 straight at home including the playoffs. With 12 wins and five ties in that stretch at RFK, there is reason to be more than optimistic this weekend.

Even for a club that could be without a plethora of starters due to injury.

Leading scorer Pontius remains questionable with a groin strain, 2011 MLS MVP Dwayne De Rosario is probable after spending months sidelined with a sprained knee, and the list goes on.

Add in the suspension to right back Andy Najar, and United coach Ben Olsen is going to have to introduce himself to the end of the bench at a time no coach wants to.

Houston also has injury concerns, and RFK could ultimately be the difference. Who would have even considered that just a few months ago?

"One of the things, when we put our goals as a team up on the board (ahead of the season), we wanted to make RFK a fortress to play in," Pontius said.

United not only made RFK a fortress, but it won five home matches this season by at least two goals. And consider, Houston - abysmal on the road during the regular season - lost by two or more goals away from home seven times.

D.C. needs a two-goal win just to force overtime, and possibly penalties, and a three-goal win would complete an impressive rally from the loss in Houston.

The reward would be a sixth appearance in the MLS Cup final. And RFK Stadium, based on United having the best record of the four teams remaining in the MLS playoffs, would host the final if D.C. advances.

D.C. claimed the second of its four MLS championships at RFK Stadium in 1997. In those days, when D.C. reached the first four MLS Cup finals and won three, RFK was feared.

Two more wins there this season would return United - and RFK - to that lofty status.

"In no way are we out of this," Olsen said.

In a hallway leading from the locker room to the field this season, a sign on the wall to reminded D.C. to "Take Back RFK."

It has never held as much meaning as it will Sunday.