It was a bad day for icons.

Three sports, three major stars either on the shelf or off the stage for good.

Kevin Garnett’s balky knee may keep him out of the NBA playoffs.

A major obstacle was just removed from the title path of the Cleveland Cavs and LeBron James. The Celts are a completely different team without KG.

KG might as well stand for “Keep Going” out of the playoffs.

NFL announcer John Madden retired after a kabillion “Booms! Whaps! and Doinks!” And about as many painfully obvious statements like “some yards are better than none yards.”

He also added enlightening verbiage to our lexicon like “turducken” and “cankles”

I guess his heart wasn’t in it anymore after his man crush, Brett Favre, called it quits ... again, this time for real.

What is Frank Caliendo going to do now?

And, finally, the Boston Red Sox lost Daisuke Matsuzaka to the World Baseball Classic, er, disabled list with a shoulder injury.

That’s what the Sox are telling us, anyway. Dice-K’s real ailment is an inflammation of the ERA.