Robbie Keane missed a penalty, meaning the Galaxy needed a late goal from Noonan to salvage a draw with FCD.
In the early going, Landon Donovan nicked the ball off Jair Benitez, rounded Chris Seitz, but saw his tight-angled shot bounce back off the post.
That same matchup played to the Galaxy's favor early in the second half as well. Donovan raced past Benitez onto a looping ball and the left back hauled the U.S. attacker down in the box. Robbie Keane shanked the penalty.
Brek Shea showed the Republic of Ireland captain how it's done. Blas Perez intercepted a chested pass from David Junior Lopes and lured the foul from backup goalkeeper Bill Gaudette. Shea didn't miss from 12 yards out.
Los Angeles equalized in stoppage time. Dallas dallied on the ball in the box, and LA's forwards managed to tip the ball back to the open Noonan, who started celebrating before his shot hit the back of the net.
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