Chief executive of Dubai-based football club Al Ahli Ahmed Khalifa is hopeful that latest acquisition Ricardo Quaresma can make a big difference to the team.The Portuguese star has joined the Pro League outfit, having been a free agent since his release from Turkish club Besiktas.Mr Khalifa told the National that he is confident Quaresma's presence will give the team a huge boost in the second half of the season.They are currently third in the league and are eight points behind leaders Al Ain."During this transfer window, it is very difficult to find players of quality like Quaresma," Mr Khalifa was quoted as saying."But we were lucky that he is a free agent. He was in Dubai, he saw the country and liked it. That made the task of convincing him a lot easier."Quaresma has had a rollercoaster career to date and has played for some of Europe's top clubs, including Barcelona, FC Porto, Sporting Lisbon, Inter Milan and Chelsea.The 29-year-old was idolised in Istanbul and he stood out for Besiktas in last season's Uefa Europa League competition.However, he left the club amid rumours of a fall-out with the managerial staff and he has now accepted a new challenge in the UAE.Dubai is steadily building a big reputation in the global footballing world and Quaresma is not the first recognisable face to head to the Gulf.Argentine legend Diego Maradona has managed in Dubai and Quaresma will join Brazilian striker Grafite - formerly of German side Wolfsburg - at Al Ahli.Ex-Sunderland hotshot Asamoah Gyan also plays for Pro League leaders Al Ain and is widely considered to be the best player in the country, although Quaresma - renowned for his skilful feet and tricky wing play - may have something to say about that.The 7th Dubai International Sports Conference was also held in the emirate last month and the event attracted a host of world-class sports stars, including Real Madrid coach Jose Mourinho, Uefa chief Michel Platini and Atletico Madrid star Radamel Falcao.