Madrid, Dec 5 : Both Real Madrid and FC Barcelona look set to lose key defenders for at least a month, with right back Dani Carvajal sidelined for Real Madrid and central defender Inigo Martinez out for Barca. Carvajal was forced out of Real Madrid's 2-0 win at home to Granada on Saturday at halftime and tests carried out on Monday have confirmed the defender has suffered an injury to his left calf, reports Xinhua. That means he will be out of action for around a month, missing La Liga matches against Betis, Villarreal, Alaves and Mallorca, a meaningless Champions League tie away to Union Berlin and the third-round tie of the Copa del Rey at the start of the year. However, if his recovery goes to plan, the Spain international will be available to play in the Spanish Supercup in Saudi Arabia in the first half on January. Carvajal joins Thibaut Courtois, Eder Militao, Eduardo Camavinga and Aurelien Tchouameni on Madrid's injury list, although Carlo Ancelotti can use either Lucas Vazquez or Nacho Fernandez as cover. Barcelona defender, Martinez was due to start their 1-0 win at home to Atletico Madrid on Sunday night, but had to pull out of the side after suffering a problem in his right hamstring. Test have confirmed the injury, and he is unlikely to play again before the end of the year, in what is a setback for the 32-year-old former Athletic Club Bilbao stopper, who had won a place in Xavi Hernandez's starting 11 and returned to the Spain national team thanks to his impressive displays over the last month. /IANS