Keio Challenger
The ATP Challenger Yokohama (official name: " Keio Challenger International Tennis " ) is taking place every since 1999 tennis tournament in Yokohama. It is part of the ATP Challenger Tour and is played on indoor hard courts. Between 2003 and 2006 and in the years 2010 and 2011, the tournament was not played.
The tournament is sponsored by the Keio Gijuku, an educational corporation that operates the Keio University, as well as elementary, middle and high schools.