John O'Brien (soccer)

John O'Brien (born August 29, 1977) is an American former professional soccer player. He primarily played as a left back or defensive midfielder.

O'Brien spent the majority of his club career in the Netherlands with Ajax, playing from 1999 to 2005. During his time with Ajax, he won the Eredivisie title in 2001-02 and the KNVB Cup in 2001-02 and 2005-06. He also played for ADO Den Haag (on loan) and later for Chivas USA and the Colorado Rapids in Major League Soccer (MLS).

On the international level, O'Brien represented the United States national team from 1998 to 2005. He was a member of the U.S. squads at the 1998, 2002, and 2006 FIFA World Cups. He earned 32 caps for the U.S., scoring one goal. He is perhaps best known for his goal against Portugal in the 2002 World Cup.