D.C. United forward Charlie Davies and teammates dance around the ball after Davies scored a second-half goal on his birthday. (Jonathan Newton/THE WASHINGTON POST)

Charlie Davies promised a memorable celebration if he scored against the Houston Dynamo in front of the home fans at RFK Stadium on Saturday, his 25th birthday. He fulfilled that when he scored in the 73rd minute to give D.C. United a one-goal lead and a chance at its first home victory in more than a month. But Brian Ching’s header in the 89th minute resulted in a disappointing 2-2 draw in an MLS match in front of 15,734.

Through 15 games of the 2011 MLS season there’s no disputing D.C. United (4-5-6, 18 points) is a vastly improved side from the one that finished last in the league a year ago. But entering Saturday’s Eastern Conference contest with Houston, D.C. had rarely displayed its growth before its home fans.

“Our ability now with the lead is just not good enough,” United Coach Ben Olsen said. “Yeah, we’re young and we don’t have the experience of playing with a lead, but the little things — the gamesmanship when we’re up in games — we’ve got a long way to go.”

Davies had had a busy week. Seven days earlier, he drew a penalty and converted the ensuing shot to earn United a draw at Real Salt Lake. Later in the week, he was hit with a $1,000 fine by the league for “putting the game into disrepute” by diving to draw the whistle that resulted in the penalty.

United’s leading scorer had three near misses in the first half Saturday — a pair of shots that slipped just outside either post and a wide-open header that Dynamo goalkeeper Tally Hall batted over the crossbar.

Midfielder Chris Pontius finally punctuated an aggressive opening half with a right-footed blast from 25 yards out — off an assist from Josh Wolff — in the 31st minute that put his team on track for its first victory at RFK Stadium since May 4.

But on a night when United conceded goals in the final five minutes of both halves, the Dynamo (4-6-7, 19 points) knotted the score at 1 in the 41st minute when Brad Davis converted on a questionable penalty drawn by Ching, who tumbled over charging United goalie Bill Hamid (five saves).

“It’s a killer when you give up a goal in the last five minutes,” Dax McCarty said. “It’s kind of been a theme for us this year — giving up goals at bad times. For us, this is a tough one to take. You go up two times in a game, you give up two goals at the end of the halves so late, it truly is a tough one to take.”

Davies finally found the back of the net in the 73rd minute, after Andy Najar dribbled into the six-yard box and Davies pounced on a loose ball and knocked it just inside the right post. He grabbed the ball, placed it at a corner flag and the team danced around it in what Davies called a “Honduras bicycle dance.”

In the 89th minute, Ching’s equalizing header from 12 yards off of a cross from Colin Clark glanced off of United defender Perry Kitchen’s head and past Hamid.

“We worked so hard to get three points at home, and for them to score in the last five minutes, it’s a terrible feeling,” Kitchen said.

United dropped to 2-2-4 at home on the season and remains one point behind the Dynamo for fourth place in the Eastern Conference standings. D.C. has two more prime opportunities to move up in the coming weeks when it hosts the Philadelphia Union and visits the New York Red Bulls.

“We really need to make RFK a place where people just can’t come in and get points and get results,” Davies said. “Two goals should be good enough to win when you play at home.”