ESPN is shutting down one of its TV networks. 

Those are nine words most people never expected to read.

But it's true. ESPN, the self-proclaimed Worldwide Leader in Sports, announced that it is discontinuing ESPN 3D by the end of the year.

Why? Sales of three-dimensional TVs just haven't taken off -- despite the popularity of the format in movie theaters.

"Due to limited viewer adoption of 3D services to the home, ESPN is discontinuing ESPN 3D," an ESPN spokesperson told the tech website Mashable.com. The service will go dark by the end of the year.

Launched with much fanfare three years ago, ESPN 3D broadcast college football and basketball games, the X Games, the Sugar Bowl and the BCS Championship, all in 3D.

But outside of ESPN, not a lot of other TV networks offered 3D programming. (Can't even think of another off the top of my head.)

But, there is hope for 3D fans. ESPN told Mashable it "will be ready to provide the service to fans if or when 3D does take off."

Roger Simmons is the executive sports editor for the Orlando Sentinel. You can reach him via email at rsimmons@orlandosentinel.com. Or follow him on Twitter at https://twitter.com/@rogersimmons. Become a fan of the Orlando Sentinel Sports Facebook page at https://www.facebook.com/orlandosentinelsports