Serena Willliams breaks a window, 'takes the fifth' on Letterman

Serena Williams stopped by the Late Show with David Letterman for a pre-U.S. Open chat, and the No. 1 tennis player in the world had her media A-game firing.

Full of energy and playful throughout the interview, Serena was stumped during an impromptu pop-quiz about her career numbers, waxed poetic about playing doubles with Venus and then invoked her Fifth Amendment rights when asked whether she's ever driven a car as fast as she can serve a ball. I guess we'll just never know. 

Letterman tests Serena about her career stats:

[youtube:http://youtu.be/5-CgZ54YtC0]

Serena talks about playing doubles with Venus:

[youtube:http://youtu.be/w2CN3JOmIio]

She then joined Letterman out on the street to show off her abs, balance and fearsome forehand while hitting some balls, including one that crashed through the window of Rupert Jee's Deli. How she doesn't topple over in those heels is a mystery to me.

[h/t: www.gfycat.com]

[youtube:http://youtu.be/9T_K-Xyc3no]