Colombia and Monaco striker Radamel Falcao faces an anxious wait to discover the extent of a knee injury that could put his place at the World Cup finals in doubt. GettyImagesRadamel Falcao is stretchered off. Falcao, 27, suffered the injury following a heavy challenge by Soner Ertek in the 40th minute of Monaco's 3-0 French Cup win at  Monts d'Or Azergues Foot on Wednesday. Earlier, he had scored the goal that gave his team the lead at the break. Monaco issued a short statement after the game, which read: "The player Radamel Falcao was hit in the left knee. He must await further tests in the coming days to clarify the exact nature of the injury." Falcao was signed from Atletico Madrid for a