Conversation so far:
Who is kevin?
Ampfield to announce that the European Footballer of the Year would be joining Southampton in the forthcoming summer.
Are there any other interesting aspects about this article?
Keegan had a clause inserted into his contract when he joined Hamburg in 1977, giving Liverpool the option to buy him back.

Question: Who else did he contract with or join?
Self-contained rewrite: Along with Hamburg, who else did Keegan contract with or join?