Lee Corso Retiring From ESPN's 'College GameDay'

It's the end of an era ... Lee Corso just revealed he's retiring from "College GameDay."

The former head coach -- who joined ESPN's legendary pregame show nearly four decades ago -- announced Thursday his last appearance on the iconic program will take place on Aug. 30, during college football's Week 1.

The 89-year-old, who will be 90 when he sits down for his finale, released a statement on his impending retirement through ESPN ... thanking all of his colleagues and fans for all of the years of support they gave him while he was on- and off-air.

"I have a treasure of many friends, fond memories and some unusual experiences to take with me into retirement," he said.

"ESPN gave me this wonderful opportunity and provided me the support to ensure success. I am genuinely grateful."

Corso first joined "College GameDay" back in 1987 ... after he had been the head coach at several major programs, including Indiana. For nearly a decade, he provided key analysis and entertaining banter -- but in 1996, he took things to the next level by making a game prediction with Ohio State's Brutus Buckeye mascot head.

The moment morphed into a weekly tradition for Corso -- and became must-see TV every week for college football fans. ESPN says in total, he's made 430 headgear picks in his career.

Kirk Herbstreit -- who sat alongside Corso for many of the coach's most memorable times on ESPN sets -- released a video Thursday congratulating his pal on all of his achievements.