Doubles for Three (Sannin no Daburusu [3人のダブルス]) is the 56th episode of the original Prince of Tennis. It originally aired on the 6th November 2002.
Due Oishi's absence, Momoshiro ends up playing doubles with Eiji Kikumaru, but the latter is unable to play to his fullest. However, once Eiji gets used to Momoshiro's presence, he begins to play in his normal play style. Oishi later shows up to cheer for them on the sidelines, encouraging the two to play to their fullest.