Uruguayan midfielder Carlos Diogo, a former player at Spanish clubs Real Madrid and Real Zaragoza, has signed a six-month contract with CSKA Sofia. Diogo, 28, who signed yesterday, will have an option to extend the deal for another two years, according to the Bulgarian club. The Uruguayan international joined Real Madrid in 2005 before transferring to Zaragoza, where he played between 2007 and 2011. CSKA Sofia currently sit second in the Bulgarian league table.