The game was an end-to-end affair in the early stages as both teams looked to open the scoring. Alejandro Mayorga forced an early save out of Stefan Frei before Clint Dempsey tested Rodolfo Cota at the other end.
Chivas came close to open the scoring just after the 30-minute mark, when a stumble by defender Roman Torres allowed Alan Pulido in one-on-one against Frei. However, the keeper was able to make a great save on the attempted chip to keep the game goalless.
At the start of the second half, Will Bruin hit the post with his header from a corner kick as it was Chivas’s turn to have a narrow escape.
But then, in the 78th minute, the hosts found the breakthrough. Dempsey found himself unmarked in the box and he finished off a cross from Henry Wingo to give the Sounders the 1-0 lead.
Chivas pressed hard for an equalizer – and a valuable away goal – in the final 10 minutes, but they were ultimately unable to find the back of the net.
With the 1-0 win, Seattle would advance with a win, a draw, or a one-goal loss – so long as they score in it – in next week’s second leg. Chivas needs a 1-0 win to send the game to extra time, and a two-goal win to advance outright.
Seattle: Stefan Frei, Chad Marshall, Roman Torres, Waylon Francis, Jordan McCrary, Clint Dempsey (Harry Shipp 90′), Cristian Roldan, Gustav Svensson, Will Bruin (Lamar Neagle 80′), Handwalla Bwana (Henry Wingo 73′), Nicolas Lodeiro.
Chivas: Rodolfo Cota, Oswaldo Alanís, Carlos Salcido, Alejandro Mayorga, Carlos Cisneros, Orbelín Pineda, Michael Pérez (José Macías 81′), Isaác Brizuela (Rodolfo Pizarro 56′), Javier López (Walter Gael Sandoval 67′), Alan Pulido, José Godínez.