Adobe Tutorial

Selective Coloring Effect in Photoshop

Before

After

Step 1: Quick selection tool to select the basketball. 
Step 2: Invert the selection (Select > Inverse). 
Step 3: New adjustment layer (from icon in the Layers Panel), select Black & White. 

Sources

Tutorial: http://www.photoshopessentials.com/photo-effects/selective-coloring/

Image: downloaded from flickr creative commons (http://www.flickr.com/photos/47611288@N00/3222971810/)