Complex sentence: Petersen joined the Titans in 2007 for their first year in the NRL but in May, 2008, he was given an immediate release to join Super league side Wakefield Trinity Wildcats.
Split into simpler sentences: Petersen joined the Titans in 2007 for their first year in the NRL. In May, 2008, he was given an immediate release to join Super league side Wakefield Trinity Wildcats.