Manchester United has completed the signing of defender Marcos Rojo from Sporting Lisbon for 20 million euros ($27 million), and sent Nani on loan to the Portuguese club. The 24-year-old Rojo, who played for Argentina in the World Cup final loss to Germany last month, has signed a five-year contract. Rojo says the ''Premier League is the most exciting league in the world and to have the chance to play in it for the world's biggest club is a dream for me.'' United's need to strengthen in defense was highlighted Saturday when the team opened the Premier League season with a 2-1 loss to Swansea in Louis van Gaal's debut as manager. The 27-year-old Nani, who joined United from Sporting in 2007, is returning there for the 2014-15 season. (For more sports news and updates, follow Ahram Online Sports on Twitter at@AO_Sportsand on Facebook atAhramOnlineSports.) http://english.ahram.org.eg/News/108882.aspx