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Shinji Okazaki's senior debut for Japan occurred at the Sapporo Dome, a well-known multi-purpose stadium situated in Sapporo, Japan. Inaugurated in 2001, this state-of-the-art facility boasts a retractable roof, making it adaptable to various weather conditions, and serves as the home venue for the Hokkaido Nippon-Ham Fighters baseball team and the Consadole Sapporo soccer club.