Complex sentence: Adrián was cleared to join Atlético Madrid on a free transfer, after it was ruled he was a free agent, and he signed on 19 July 2011 after agreeing to a four-year contract.
Split into simpler sentences: Adrián was cleared to join Atlético Madrid on a free transfer, after it was ruled he was a free agent. He signed for the club on 19 July 2011, agreeing to a four-year contract.