Wayne Rooney has been ruled out for another two weeks.

The Manchester United striker sustained a minor knee injury in training on Christmas Day and Sir Alex Ferguson initially expected him to be back in a fortnight. However, it now seems he will be missing for longer and is set to sit out next week's clash with Liverpool.

"Wayne is still injured," Ferguson said. "It is not serious but it is going to take longer than we thought, probably another two weeks. He won't be fit for Liverpool."

Rooney was expected to have been back in training by now and Ferguson is not sure why it has not happened. "He got a little kick behind his knee and he is still feeling it," the United manager said. "Hopefully another couple of weeks will sort it out. Nonetheless, it is a loss. You always want your best players available."

There was some good news for United, though, with Ferguson revealing that the winger Nani, who has been absent for two months with a hamstring problem, will take a major step forward in his recovery. "He starts training today," he said.