WASHINGTON — D.C. United and the Chicago Fire both extended unbeatenstreaks by playing to a scoreless tie Saturday night.

United (16-6-7) is unbeaten in its last 13 MLS games. The Fire (9-10-10)have a seven-game unbeaten streak. It was the first time D.C. failed to scoresince losing 1-0 at New York on July 22, the game before United started itsstreak.

United goalkeeper Troy Perkins had a season-high nine saves. He tied hisprevious season high of eight in the first half.

His final save came on one of the Fire’s most dangerous shots of the night,when Chad Barrett took the ball from a defender and fired a hard shot from thetop of the penalty box in the 54th minute.

United’s closest scoring chance came early, when Guy-Roland Kpene hit theleft post in the 16th minute.

Both teams started out aggressively but played more cautiously in the secondhalf, with just one shot on goal for each team after halftime.

United, trying to win the MLS Supporter’s Shield for the second straightseason, remains on top of the league standings with 55 points with one gameremaining. Chivas USA has 52 points with two games left. Chicago remains inposition for the eighth and final playoff spot with one game left.