PRINCETON, Texas (CBSDFW.COM) – Former football player John Blake, whose coaching stints ranged from high school to the NFL, has died at the age of 59, officials announced.

Most recently, Blake was a teacher and coach at Princeton High School in Collin County. The district announced his passing and said he had been recently diagnosed with a heart condition.

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“It is with deep regret that we inform you about a loss to our school community. Beloved long-time teacher and coach John Blake passed away early this morning,” Princeton ISD said in a statement. The district said he had been with the school since 2012.

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Blake served multiple roles during his coaching career. He was a defensive line coach for the Dallas Cowboys from 1993 to 1995 and then became head coach of the Oklahoma Sooners. He led OU from 1996 to 1998.

His coaching career also took him to the University of Nebraska, University of North Carolina and the NFL’s Buffalo Bills.

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Princeton ISD says services for Blake are pending.