Chivas USA goalkeeper Dan Kennedy salvaged 2 draw against D.C. United.
The home side scored the lone goal of the first half as De Rosario headed home a free kick from Andy Najar six minutes before the break.
United doubled its lead shortly after the restart when a corner kick to the back post was volleyed on goal by De Rosario. Kennedy made the initial save but Ethan White followed up the rebound and scored his first MLS goal from close range.
However, Juan Pablo Angel dragged his team back into the match in the 57th minute when he latched on to Nick LaBrocca's cross to redirect the ball past goalkeeper Bill Hamid from six yards.
It took the Colombian just 12 minutes to level the contest as he found his second goal from a cross by Ante Jazic. The ball was loose inside the area and Angel pounced quickly to knock it past Hamid and inside the right post.
Chivas substitute Laurent Courtois had a great chance to put his team in front in the 87th when he was released into the area on the left by Justin Braun, but he shot straight at Hamid.
Three minutes into stoppage time, Angel was called for a push on De Rosario inside the penalty area, but the United man saw his spot kick saved at the right post.
Chivas is now winless in its last seven matches, while United has earned four points from its last four games.