Watch: Wawrinka smashes opponent's family jewels

"Quiet please, balls in play."

Former Australian Open champ Stan Wawrinka rushed to the aid of opponent Martin Klizan during the fifth set of Sunday's opening-round victory, and for good reason, after the Stanimal returned the Slovak's half volley with a blistering smash to the family jewels.

Klizan was momentarily in some pain as Wawrinka tended his adversary-cum-victim before the match continued, with the fourth-seeded Swiss winning 4-6, 6-4, 7-5, 4-6, 6-4.