Bob is tapping his tennis shoe at it and seems to be making it angrier.

NPR: Recording Story Rattles Producer

Oswell's go-to shoe for everyday wear is a pair of tennis shoes.

CNN: Flip-flops present feet with a painful problem

Tennis has a reputation as a sport for elites, favored by the white-shoe, country club set.

FORBES: Magazine Article

The shoe and apparel deal is almost always the largest endorsement for top players in tennis.

FORBES: World's Highest-Paid Tennis Players