Complex sentence: Fagan started his career as a teenager at Celtic and moved on to Preston where he would link up with future Anfield managerial great Bill Shankly who was playing for the club at the time.
Split into simpler sentences: Fagan started his career as a teenager at Celtic. He moved on to Preston where he would link up with future Anfield managerial great Bill Shankly who was playing for the club at the time.