What was the first Pokémon game to use Nintendo Wi-Fi Connection for online play?

Pokémon Diamond and Pearl were the first Pokémon games to use Nintendo Wi-Fi Connection for online play.

Released for Nintendo DS in Japan in 2006, Diamond and Pearl allowed players to trade and battle through Nintendo’s online service. Earlier games supported local communication, including Game Boy Link Cable features and later wireless functions, but Diamond and Pearl made internet-based player interaction a core main-series feature.

The Nintendo DS hardware helped enable this change. Its built-in wireless connection and online service allowed players to interact beyond the same room, expanding the series’ long-standing emphasis on trading and battles between friends.

Nintendo Wi-Fi Connection was discontinued in 2014, so the original online services for Diamond and Pearl are no longer available. Modern Pokémon games use newer network systems, but the fourth-generation titles remain historically important for bringing official online connectivity to the main series.