Mississippi State confirmed its head coach passed away on Monday night -- just one day after he was rushed to a hospital in Jackson, Miss. after suffering a "personal health issue at his home."

The school said his death was due to "complications from a heart condition." No further details were released.

He was 61 years old.

"Mike was a giving and attentive husband, father and grandfather," the Leach family said in a statement. "He was able to participate in organ donation at UMMC as a final act of charity."

"We are supported and uplifted by the outpouring of love and prayers from family, friends, Mississippi State University, the hospital staff, and football fans around the world. Thank you for sharing in the joy of our beloved husband and father's life."

Leach initially began his college coaching career in 1987 ... and eventually landed his first D1 head coaching role over a decade later when he became the head man at Texas Tech in 2000.

Leach famously implemented a pass-heavy offense that was later dubbed the "Air Raid," which many college coaches now run at schools to this day.

Following 10 seasons at Texas Tech -- where he compiled an 84-43 record -- Leach signed on to coach Washington State in 2012. He spent eight seasons there ... before moving to Mississippi State in 2020.

Nicknamed The Pirate, Leach gained national fame and fans for his dry sense of humor and quirky responses at media events.

Mississippi State University president Mark E. Keenum mourned the loss on Tuesday morning ... writing in a statement, "Mike's keen intellect and unvarnished candor made him one of the nation's true coaching legends. His passing brings great sadness to our university, to the Southeastern Conference, and to all who loved college football. I will miss Mike's profound curiosity, his honesty, and his wide-open approach to pursuing excellence in all things."

In his 21 years as a head coach, Leach compiled a record of 158-107 ... and won eight bowl games.