Manchester United manager Sir Alex Ferguson has ruled out a January transfer window spree, despite a mounting injury crisis at his club. Midfielder Darren Fletcher this week became the latest player to join United\'s casualty list, which already includes captain Nemanja Vidic, who will miss the rest of the season, and striker Javier Hernandez. But despite calls for Ferguson to bolster his squad, with particular concern over the midfield, the United manager said he will only buy if the right player becomes available. Asked if he expected United to sign any new players next month, he explained: \"Not neccessarily. I don\'t know why people keep going on about it. [I won\'t buy] unless someone we have always been interested in appears, but there isn\'t.\" Ferguson meanwhile said United had felt compelled to go public with the details of Fletcher\'s illness after the midfielder was revealed to be suffering from the bowel condition ulcerative colitis. The club had previously explained Fletcher\'s condition as a virus. \"That was the big decision,\" Ferguson said. \"It got to the point where we had to address it in a different way. We spoke about a virus to protect Darren but it got to the point people were delving. It was getting uncomfortable so we decided to make it public. He has been in hospital for a few days.\"