Serena forehand destroys Rupert's storefront window on 'Letterman' (VIDEO)
AUG 22, 2014 9:52a ET
In town to defend her U.S. Open singles title (again), Serena Williams visited the "Late Show with David Letterman," where she had a friendly rally with the host Thursday before shattering beloved Rupert Jee's Hello Deli window.
Whatever those windows are made from -- glass, Plexiglas -- clearly they were not designed to withstand 80- to 90-ish mph bullets from a tennis pro. And she did it in heels, no less.
Williams will face a human, Taylor Townsend, in the first round of the tournament.