Tigres UANL land the two defenders on loan from Club America.
Castillo, the American-born defender, is reunited with former Santos Laguna manager Daniel Guzman. Now at Tigres' helm, Guzman went for his former star left back to help Tigres stay in the Primera Division.
During his short-lived stint with America - Castillo left Santos following the Apertura 2008 season - he had a falling-out with manager Jesus Ramirez.
"Fernando Ortiz and Edgar Castillo, both defenders, are two more reinforcements for Tigres UANL for the 2009-2010 season," the club said in a statement. "The two players join the club on loan for a year with an option to buy and will report to our training camp in a matter of days."
Tigres debut in SuperLiga on June 20 at Chivas USA but it is uncertain if either player will compete for their new team at that time.
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