diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
index 2a8807fb78647..07b122efd1ca5 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
@@ -211,6 +211,7 @@ def self.establish_connection(spec = nil)
           clear_active_connection_name
           @active_connection_name = name
           @@defined_connections[name] = spec
+          connection
         when Symbol, String
           if configuration = configurations[spec.to_s]
             establish_connection(configuration)