Mike Krzyzewski's retirement tour has, at most, one more month. The legendary coach of the Duke Blue Devils is retiring after this season, ending one of the most famous and successful coaching careers ever. “Coach K” has five national championships and the most wins ever in Division I men's basketball history to his name.

One of the less-heralded parts of his career centers around a letter from famous coach Bob Knight. As Krzyzewski tried to break free from Knight's shadow, Duke beat his Indian Hoosiers in a 1992 Final Four contest. Knight gave Coach K a weak handshake after the game and had one of his assistants deliver a letter from him. It essentially ended their relationship in brutal terms.

According to ESPN's Wright Thompson, Duke assistant coach Mike Brey issued a strong message towards Knight to help console him.

After that 1992 win over Indiana, with a Michigan game looming in 48 hours for a second straight national championship, the Knight letter dominated the insular Duke ecosystem. Krzyzewski got back to his hotel suite in a fog, just totally devastated. Current Notre Dame head coach Brey, then an assistant, remembers how they were trying to work and Coach and his wife kept bringing up the letter, trying to make sense of their hurt. Finally Brey knew he needed to do something. He stood up and spoke simply.

“F— Bob Knight,” he said.

This was a crazy stance for Brey to take considering Knight was Krzyzewski's college coach at Amry West Point and the two had a great relationship until then. Krzyzewski ultimately took the words to heart and helped lead Duke to its second-consecutive national title.

With former Duke standout Jon Scheyer ready to take the reigns from him next season, Mike Krzyzewski leaves behind an unprecedented coaching legacy.