Edgar Eduardo Castillo Carrillo[a] (born October 8, 1986) is an American former professional soccer player who played as a left-back.

Castillo grew up in Las Cruces, New Mexico, and played for Mayfield High School under coach Arturo Garibay.

He was one of the top players in New Mexico as he helped lead Mayfield High School to two state championships games [clarification needed].

He first gained the notice of professional teams in 2005 playing for his local club in the Dallas Cup, one of the world's top youth tournaments.

His younger brother, Noel Castillo, is on the reserve team for Indios de Ciudad Juárez of Mexico.

After becoming a first team regular at Santos, and winning the championship in 2008, Castillo transferred mid-season to Club América in January 2009.

[7] On January 17, 2020, Castillo made the move to Atlanta United[8] after his option was declined by New England at the end of the 2019 season.

[12] In early August 2007, Mexico coach Hugo Sánchez called-up Castillo for the three upcoming friendlies with Colombia, Panama, and Brazil.

In March 2008 he was also a member of the Mexico U-23 squad which participated in the 2008 CONCACAF Men Pre-Olympic Tournament in order to qualify for 2008 Summer Olympics.

"When I changed to the U.S. national team, it was a hard time for me because people called me a traitor and stuff like that," Castillo remarked.