Brad Evans also scored for the Sounders (8-7-4), who are unbeaten in their last eight games at home (4-0-4) to tie a franchise record. Seattle's only home loss was 1-0 to Montreal in the season opener.
Erick Torres tallied late in the 16th minute for Chivas (4-12-5), which was playing for the first time since it snapped a 14-game winless streak on July 17.
Obafemi Martins started the play on the game-winner when he sprinted down the right side to catch up with the ball just inside the box. He sent it across to Mauro Rosales on the penalty spot. Rosales, as he was falling down, tapped it to his left to Neagle, who drilled it past goalkeeper Dan Kennedy into the back left corner of the net from 13 yards out for his fifth goal of the season.
It was the first time since Sept. 8, 2012, — also a 2-1 victory against Chivas — that the Sounders came back to win after allowing the first goal of the game. They had been 0-9-1 when the opponent scored first.
Chivas took a 1-0 lead when Carlos Alvarez got past two Seattle defenders and tapped the ball to his left. Torres ran onto it, and from 14 yards out fired it across the penalty area and past Sounders goalkeeper Andrew Weber into the back right corner.
That was the second goal in two games for Torres, who scored in his MLS debut on July 17 to beat Toronto, 1-0.
Rosales and Martins factored into Evans' tying goal. Controlling the ball along the right sideline, Rosales crossed it to Martins. He sent a through ball toward the top of the box and Evans ran onto it, sending it to the back left corner for his second of the year.
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