In the midst of another year of regression for his South Carolina football team, head coach Steve Spurrier decided to call it a career.

Citing unnamed sources, Sports Illustrated learned Spurrier's retirement would be effective immediately. It is not clear what exactly led to Spurrier's abrupt retirement, as neither the school nor the coach has confirmed the news.

ESPN later confirmed the story, citing its own sources and also noted the coach's weekly press conference is scheduled as usual for Tuesday at noon.

Spurrier leads all South Carolina head football coaches in wins and also boasts an impressive .715 winning percentage in the college game. However, the Gamecocks broke their streak of three straight 11-win seasons with a seven-win effort last season. This season, South Carolina is 2-4, having lost its last four SEC games, and would have to win out just to get to eight wins overall.

Spurrier became known for his penchant for quips and off-the-cuff jabs, often aimed at agitating his rivals. But many of his peers expressed respect for the coach and sadness that college football would be losing him.

Coach Spurrier has impacted & influenced more of us in this business than he will ever know. He will be missed and will always be the "HBC"

— Hugh Freeze (@CoachHughFreeze) October 13, 2015

Thank you, Coach Spurrier, for paving the way and showing us all what greatness truly is. #GoGators #HBC https://t.co/IHyB2loloX — Jim McElwain (@CoachMcElwain) October 13, 2015

"I hate it for Steve and hate it for college football," Alabama head football coach Nick Saban told ESPN. "The guy's been one of the best coaches for a long, long time and a great personality for the game. I have a tremendous amount of respect for what he's accomplished and what he's done... It's always sad to see somebody who's meant so much to the game walk away."

Following South Carolina's 7-6 season last year, Spurrier indicated he was contemplating retirement and said he wanted "two or three" more years. A few months later, he rejected the idea that he was nearing the end of his career due to ineffectiveness brought on by age.

"He's probably the most competitive guy I've ever known, but he's also one of the most genuine guys I've ever known," Oklahoma head football coach Bob Stoops told ESPN. "He's special."