Stefanos Tsitsipas has some serious explaining to do.
An irate Tsitsipas erupted in son-stroke accidentally nailing his father, Team Greece captain Apostolos Tsitsipas, while smashing his racquet in frustration at the ATP Cup in Brisbane.
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Fatherhood can be a hazardous occupation.
Watch Apostolos Tsitsipas cringe as his raging son smashes a court-side sign then recoil in pain when Stefanos Tsitsipas inadvertently hits his father's right arm while swinging his racquet at the bench.
A stunned Apostolos Tsitsipas, clutching his right forearm in apparent pain from the bruising blow, stands up, speaks to his son and walks off.
Family conflict did not end with that strike.
Watch as Stefanos' mother, former WTA pro Julia Salnikova, leans over to chew her son out for his transgression.
Adding insult to his dad's injury, Tsitsipas lost to Nick Kyrgios in a thriller 7-6(7), 6-7(3), 7-6(5) as the theatrical Aussie pulled off some audacious drop shots in the decisive tie break.
Afterward, Tsitsipas sat alone on the team bench perhaps contemplating the punishment he may well face from his parents.
He later talked to reporters and told them:
"I wasn't aiming to do that. It just went out of control, unfortunately." He added that he may be grounded. "Maybe I'll stay in my room for three days--grounded by my father."