March 2011, Duff scored a brace in a 3–2 win against former side Blackburn Rovers at Craven Cottage. With the two goals, he continued a run of four goals in five matches. About Fulham and his time at the football club, Duff stated: "I like to think that I have found my feet again here at Fulham. It's a good environment and one that players feel very comfortable in. This is a club with so much character and I'm very happy to be helping move it forward." At the end of the 2010–11 season, Duff made 27 appearances and scored 4 goals in all competitions, including making 24 Premier League appearances. On 19 August 2011, Duff signed a one-year extension to his current deal. After nine goalless matches, Duff scored in Fulham's 2–1 win over Norwich City on 31 March 2012. A week later, on 7 April 2012, he starred in Fulham's 0–3 away win over Bolton Wanderers, setting up Clint Dempsey for the second goal of the match. During the match, which marked his 350th league appearance, he was a constant threat on the right wing. On 18 August 2012, Duff scored the opening goal in Fulham's 5–0 win over Norwich City on the opening day of the 2012–13 Premier League. He scored again in the following game, a 3–2 defeat to Manchester United. On 22 February 2013, Duff signed a new contract with Fulham, keeping him at the club until summer 2014. On 16 April 2014, Duff confirmed his intention to leave Fulham at the end of the 2013–14 season. Duff told The Irish Times, "I'll be leaving Fulham. The club haven't spoken to me and I haven't spoken to the club but we don't need to speak." He was released from the club on 23 May. Melbourne City In June 2014, Duff joined Australian A-League club Melbourne City as a free transfer in a one-year deal. Duff made his debut against Sydney FC on match day one, assisting David Villa for his first goal in the A-League. Duff scored his first goal against the Newcastle Jets in a 5–2 win. In March 2015, Duff confirmed that he would leave Melbourne City to return to his homeland, with the intention of finishing his career in the League of Ireland. Shamrock Rovers On 14 July 2015, Duff signed for League of Ireland Premier Division club Shamrock Rovers, and revealed