Marion Bartoli reacted to Serena Williams' tennis quiz question.

The question was, “In tennis, what is the name of the shot where a player strikes the ball before it bounces twice?” Serena answered incorrectly with volleying. The correct answer was actually “a half-volley.”

Marion Bartoli took to Twitter to comment on Serena Williams’ answer. She said, “Serena Williams is one of the greatest tennis players in history and yet she doesn’t know the difference between volleying and a half volley… I can’t believe it!”

Bartoli added that Serena should have known the answer to the question, as it is “one of the most basic shots in tennis.” However, Serena responded with good humor, tweeting back at Bartoli that she was “just having a bad day.”

The exchange proved to be light-hearted and humorous for fans of both Serena Williams and Marion Bartoli, showing that the two tennis stars still have a good relationship and can joke around with each other.

Serena surely did not need to prove her tennis knowledge to anyone as she is one of the most successful players in history. Nevertheless, it was a fun exchange between the two Grand Slam champions.

Although Serena Williams may not have known the answer to this particular tennis question, there is no doubt that she has cemented her legacy as one of the greatest players ever.

Serena and Marion Bartoli continue to be great role models for aspiring young tennis players around the world. Their fun exchange on Twitter only adds to their legacies as two of the sport’s greatest stars.