Diamond Stadium

Diamond Stadium is a location in the anime series Sonic X. It is a baseball stadium located in Station Square. The field is owned by Elmer Johnson who wanted to build an indoors stadium, resulting in demolishing Diamond Stadium. The stadium is well-known for its beautiful turf.

Past
Diamond Stadium was the former playing grounds of the Diamond baseball team that was seemingly abandoned for around thirty years. During this time though, the groundskeeper, Albert Butler has been maintaining the field.

New World Saga
Miles "Tails" Prower first visited the stadium, meeting Albert and learned about the stadium's history and sadly, Albert tells Tails that the stadium's impending demolition due to Elmer Johnson wanting to build an indoors stadium. Albert then shows his Chaos Emerald to Tails who also possess another one. Due to their close proximity, a bright light was emitted from the Chaos Emeralds and shot straight into the sky which brought everyone's attention, including Dr. Eggman, Sonic and his friends.

Dr. Eggman arrived at Diamond Stadium in an attempt to snatch the two Chaos Emeralds from Albert and Tails but Knuckles, Sonic and his friends managed to keep one safe. Dr. Eggman challenged Sonic and his friends to a winner-takes-all baseball game in an attempt to claim both Chaos Emeralds using a team of several E-21 Ballios robots. Initially, Eggman's team weren't playing fair but Sonic's team eventually edged into the lead. Throughout the game, the stadium was suddenly filled with citizens. Sonic's team won but Dr. Eggman escaped with the Chaos Emerald along with his Ballios robots.

As the crowd cheered wildly for the victory of Sonic's team, Elmer Johnson appeared and thanked Albert for his hard work and dedication to the stadium. The fate of Diamond Stadium differs between the Japanese and English versions of the episode; in the English version, Elmer Johnson decides to take the turf out of Diamond Stadium and put it in a new stadium requiring Albert's help, while in the Japanese version, he commits the stadium itself to Albert's care.

Emerl Saga
The Diamond Stadium was the location of the Chaos Emerald Martial Arts Mash-Up, a martial arts competition, during the episodes "Prize Fight" and "A Wild Win". In these episodes, the stadium has been converted from a baseball field and now features a raised arena in the middle.