Sumo Wrestling

On February 23, 2010 the Sumo Association announced that it had changed its definition of "foreign" to "foreign-born" (gaikoku shusshin), meaning that even naturalized Japanese citizens will be considered as foreigners if they were born outside Japan. The restriction on one foreign wrestler per stable was also reconfirmed.
Professional sumo tournaments
There are six Grand Sumo tournaments (or honbasho) each year: three at The Sumo Hall (or Ryōgoku Kokugikan) in Ryōgoku, Tokyo (January, May, and September), and one each in Osaka (March), Nagoya (July) and Fukuoka (November). Each tournament begins on a Sunday and runs for 15 days, ending also on a Sunday. Each wrestler in the top two divisions (sekitori) has one match per day, while the lower ranked rikishi compete in seven bouts, approximately one every two days.