In a round 20 match towards the end of his final season (2006) with the Roosters, Morley was sent off after attempting to knee Bulldogs player Corey Hughes in the face as the player attempted to play the ball. Afterwards he was suspended by the NRL judiciary and the Sydney Roosters released him from his contract. He returned to the UK before the season's end. Morley had helped Sydney Roosters to a World Club Challenge title as well as two further Grand Final appearances before rejoining English club, Warrington. He is one of only eight Englishmen to have played in Australian National Rugby LeagueGrand Final winning teams. Morley became the only player to win Great Britain caps whilst at Sydney Roosters, although Phil Clarke had won England caps whilst at Sydney City Roosters. With a property in Sydney's eastern beach suburbs, and an English partner, rumours are rife that Morley will return to Australia to retire in the sun at the end of his career – not before playing a season or two to conclude his top flight profession as a Rugby League player, with Sydney Roosters.
In 2005 Adrian Morley became the first Englishman to complete the 'rugby league trifecta', winning Premierships in both the National Rugby League, Super League and also winning the Rugby League Challenge Cup. In late 2005, although still contracted to Roosters; Morley joined Bradford at the backend of the season and helped them to claim the Super League championship against his old team Leeds. He played for the Bradford Bulls from the interchange bench in their 2005 Super League Grand Final victory against the Leeds Rhinos. His stay at Bradford was short stayed as he joined Warrington the year after
Morley signed a 4-year deal with Warrington, beginning in 2006. He made his Warrington debut against Wigan on 9 February 2007 but lasted only 37 minutes after an accidental clash of heads with Wigan'sEamon O'Carroll which resulted in Morley having surgery on a fractured eye socket. Five rounds later Morley made his home debut and comeback against Hull Kingston Rovers. Another clash of heads resulted in Morley leaving the field after only 16 minutes with a displaced fracture of the left cheekbone. He captained the Great Britain test side that faced France in 2007. He was also appointed captain of Warrington. It was while playing for Warrington that he made his 400th competitive senior appearance in Rugby League.
Morley signed a one-year deal for his hometown club Salford for the 2014 season. Morley spoke about wanting to finish his career with his hometown club and now he will get the chance to do so. The 36-year-old forward was appointed the Red Devils captain at the start of the 2014 season.
On the 10th of September 2015, Adrian announced that he would retire from playing rugby league at the end of the 2015 season.
On October 14 2015, It was announced that Morley would play one more rugby league match. In his last match, he represented his debut club, Leeds, in a one-off exhibition game against New Zealand.