Sergio Aguero, who was substituted in the opening minutes of Manchester City’s 1-0 win at home to Everton on Saturday, has suffered a knee ligament injury and has already been ruledout City’s crucial UEFA Champions League clash with AS Roma in Italy on Wednesday, coach Manuel Pellegrini told reporters after the game. While the long-term prognosis for the Argentinestriker is still uncertain, Sky Sports is reporting that he will be sidelined for a minimum of four weeks. The injury could not have come at a worse time for City, as the club’s otherforwards, Edin Dzeko, David Silva and Stevan Jovetic, are also struggling for fitness.