UNITED'S injury crisis has now taken a mysterious twist with Nemanja Vidic back on the casualty list. The Reds' defensive woe had appeared to be on the upturn with Jonny Evans back in the rearguard for the FA Cup tie against Leeds. The Northern Ireland international had been out of action since the end of November at Portsmouth with an ankle problem. He had missed eight matches but was originally paired with Vidic to face Leeds. However, the big Serbian defender was reported to have "felt something" in the warm-up before the game and was withdrawn from the Reds' original team sheet. Wes Brown, who had been rested, was rushed into action and promoted from the bench with Antonio Valencia, who didn't figure at all in the 18 on Cup duty, making an emergency appearance among the subs. But it was Fergie's curt response to a question about Vidic that suggested his patience is wearing thin. When asked what was the matter with Vidic a stony-faced United boss replied: "I couldn't tell you. I couldn't tell you at all." Vidic has been troubled with a calf injury since October but Ferguson was singing the praises of his return to action post-Christmas against Hull and Wigan saying that the Brown-Vidic axis gave the Reds a solid platform for back-to-back victories. Vidic's name has been linked all campaign with a move to Barcelona and there have been reports of behind the scenes unrest though the 28-year-old has consistently said publicly that he is happy at Old Trafford. What do you think? Have your say.