diff --git a/blackjackbot/commands/game/commands.py b/blackjackbot/commands/game/commands.py
index 428b16e..5b25a09 100644
--- a/blackjackbot/commands/game/commands.py
+++ b/blackjackbot/commands/game/commands.py
@@ -115,6 +115,8 @@ def join_callback(update, context):
 
     try:
         game.add_player(user.id, user.first_name)
+        # Players joining a group game never sent /start, so they might not be stored in the database yet
+        Database().add_user(user.id, user.language_code, user.first_name, user.last_name, user.username)
         update.effective_message.edit_text(text=translator("mp_request_join").format(game.get_player_list()),
                                            reply_markup=get_join_keyboard(game.id, lang_id))
         update.callback_query.answer(translator("mp_join_callback").format(user.first_name))
diff --git a/blackjackbot/commands/game/tests/commands_test.py b/blackjackbot/commands/game/tests/commands_test.py
new file mode 100644
index 0000000..82c34f1
--- /dev/null
+++ b/blackjackbot/commands/game/tests/commands_test.py
@@ -0,0 +1,43 @@
+# -*- coding: utf-8 -*-
+import unittest
+from unittest.mock import Mock, patch
+
+from blackjack.game import BlackJackGame
+from blackjackbot.commands.game.commands import join_callback
+from blackjackbot.gamestore import GameStore
+
+
+class GameCommandsTest(unittest.TestCase):
+
+    @patch("blackjackbot.commands.util.decorators.Database")
+    @patch("blackjackbot.commands.game.commands.Database")
+    def test_join_callback_stores_user(self, db_mock, decorator_db_mock):
+        """Players joining a group game via the join button must be stored in the database, so their stats are tracked"""
+        db_mock.return_value.get_lang_id.return_value = "en"
+        decorator_db_mock.return_value.get_lang_id.return_value = "en"
+        chat_id = -1004321
+
+        game = BlackJackGame(gametype=BlackJackGame.Type.MULTIPLAYER_GROUP)
+        game.add_player(1, "A")
+
+        game_store = GameStore()
+        game_store.add_game(chat_id, game)
+        self.addCleanup(game_store.remove_game, chat_id)
+
+        update = Mock()
+        update.effective_chat.id = chat_id
+        update.effective_user.id = 2
+        update.effective_user.first_name = "B"
+        update.effective_user.last_name = "Bee"
+        update.effective_user.username = "bbb"
+        update.effective_user.language_code = "de"
+        update.callback_query.data = "join_{}".format(game.id)
+
+        join_callback(update, Mock())
+
+        self.assertEqual(2, len(game.players))
+        db_mock.return_value.add_user.assert_called_once_with(2, "de", "B", "Bee", "bbb")
+
+
+if __name__ == '__main__':
+    unittest.main()