The Serbian's late withdrawal had led to suggestions that Ferguson was unhappy with the former Spartak Moscow defender, who has emerged as a £20m summer target for Real Madrid.
Related ArticlesBirmingham v Man Utd: match previewFerguson: Neville retirement 'a load of nonsense'Ferguson heaps praise on McLeishGiggs to receive freedom of SalfordBut the Manchester United manager, whose team are due to face Birmingham at St Andrews tomorrow evening, admits that Vidic is facing a short lay-off with his injury.
Ferguson said: 'Vidic felt a problem with the nerve in the right side of his leg before the Leeds game.
'It has been a bit of a problem recently and he didn't feel confident to play. I can understand that because it can be quite painful.
'We sent him to see a specialist on Wednesday and he was able to diagnose the problem.
'It is down the exercises he has been doing, so Nemanja has been given a programme which he will be able to do over the next ten days.
'It isn't long-term, we can control it and hopefully he will be back quickly.
'Wes Brown and Jonny Evans are both available, so that's good news and Rio is doing good work is not far away. He should be back in full training within two weeks.'
Temperatures at United's Carrington training ground were as low as a punishing minus 13 degrees at 9am this morning and Ferguson admits that training has been difficult this week.
He said: 'I have never known anything like it. This is Aberdeen weather.
'The players have had two days off and then trained on Wednesday afternoon in the gym, which wasn't ideal.
'Most of the players couldn't get off their driveways and (assistant manager) Mike Phelan was snowed in in Burnley.
'It hasn't been easy, but we are trying to clear a pitch so that we can train outside this afternoon.'