diff --git a/include/game_state.h b/include/game_state.h
index 8b03a2d..b1acc26 100644
--- a/include/game_state.h
+++ b/include/game_state.h
@@ -119,15 +119,6 @@ namespace Hanabi {
     }
 }
 
-namespace std {
-    template<>
-    struct hash<Hanabi::Card> {
-        std::size_t operator()(Hanabi::Card const& card) const noexcept {
-            return card.suit * 6 + card.rank;
-        }
-    };
-}
-
 namespace Hanabi {
 
 inline std::string to_string(const Hanabi::Card &card);