Tennis

Tennis is a racquet sport played on Earth. K-9 erased all his knowledge of tennis from his memory banks, when he followed Romana's instructions to "forget it" literally. (DW: The Stones of Blood) Later in the Doctor's life,  Jack Harkness was seen trying on a tennis outfit complete with racquet for a tv show but did not seem to like it claiming it was 'too safe'. (DW: Bad Wolf) Still later, the Doctor used a tennis racquet to hit General Staal's Probic vent. (DW: The Sontaran Stratagem)