There was a time when you'd see her knocking about in Adidas, but those days are presumably over. 
The youngest of the Kardashian clan made her debut for Puma over the weekend, and this is the shot she chose to post to Instagram. She captioned the shot: "Excited to reveal my campaign for the @PUMA Fierce, a lightweight trainer with zero excuses, available starting 4/1 on PUMA.com, PUMA retail stores, and select retailers worldwide. The next level starts here #ForeverFierce."

Prepare yourselves to see these pants being sported around town A LOT this summer.

She's so committed to her new role that she even dyed her hair navy - sorry, "midnight blue" - to compliment the above look... We are of course jesting; these publicity shots were probably taken before she broke out her new doo yesterday.