SEATTLE — Clint Dempsey scored for the third straight game on a first-half header and set up Gyasi Zardes for a tap-in goal midway through the second half, boosting the United States into the Copa America semifinals with a 2-1 win over Ecuador on Thursday night.

Playing before a boisterous and almost completely partisan home crowd in the soccer-mad Pacific Northwest, the U.S. won a knockout game against a nation outside its region for only the second time and will play Argentina or Venezuela on Tuesday in Houston.

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American midfielder Jermaine Jones and Ecuador winger Antonio Valencia were both ejected early in the second half. Jones will be suspended for the semifinal along with U.S. midfielder Alejandro Bedoya and Bobby Wood, who both got their second yellow cards of the tournament.

Dempsey’s 52nd international goal, five behind Landon Donovan’s American record, put the U.S. ahead in the 22nd minute and Zardes guided Dempsey’s cross into the net in the 65th for a 2-0 lead.

Michael Arroyo scored for Ecuador in the 74th minute and Enner Valencia missed a pair of great chances moment later on a pair of headers.