Complex sentence: The following season he helped "the Seasiders" win promotion to the First Division and then ater they were relegated in he was part of the Blackpool team that won the Anglo-Italian Cup beating Bologna in the final in Rome.
Split into simpler sentences: The following season he helped "the Seasiders" win promotion to the First Division. After they returned whence they had come, he was part of the Blackpool team that won the Anglo-Italian Cup beating Bologna in the final in Rome.