New York won with Marquez in the line-up for the first time since April 30 to move back into the play-off spots and prevent LA from sealing the Supporters' Shield.
The game, rescheduled due to Hurricane Irene, was vital for New York's play-off efforts, while the Galaxy fielded a weaker side with Landon Donvoan and Robbie Keane missing out with injury and international duty, respectively.
Still, New York coach Hans Backe described the Red Bulls performance as the "best well-balanced game since before the Gold Cup" and noted that his side "got better and better throughout the 90 minutes".
Extended pressure paid off when New York opened the scoring in the 32nd minute through Luke Rodgers. The Red Bulls sent in a corner, initially headed goalwards by Jan Gunnar Solli. Galaxy keeper Donovan Ricketts produced a nice reaction save, but Rodgers immediately deflected the ball back into the goal.
Just five minutes later, Henry squared a pass to a wide open Luke Rodgers who ringed a sitter off the left post.
Henry tallied his joint-league-leading 14th goal on the hour mark. The highly scrutinised Rafael Marquez played an early ball forward from behind the midfield line. Galaxy defender AJ DeLaGarza let the ball bounce with Henry in the vicinity. The Frenchman finessed a chip over the sliding Donovan Ricketts.
Henry hit the post in the 81st minute after stripping David Beckham, who otherwise had a quality performance. The Frenchman was in on goal when his angled shot beat keeper Ricketts, but not the post.
The full-time whistle blew and LA remains two points away from clinching the Supporters' Shield.
"It was a great team performance. It's a massive, massive boost for us," Luke Rodgers said.
New York went with two holding midfielders, Marquez and Teemu Tainio, in front of the back four. The 2-0 result marked the first win with Marquez in the side since April 30 for New York.
"It's a safe way to play, but it's solid for us," Backe said of his lineup.
"They read the game at a different level back there," defender Stephen Keel said of the duo.
New York seem to be hitting their stride at the right time, claiming 10 points from their last five games. The Red Bulls are now up to ninth in MLS, back into the playoff positions. Chivas USA and the San Jose Earthquakes were eliminated from postseason contention by the result.
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