The Rams led 1-0 from the first leg but a fierce Nani strike levelled the tie and defensive errors let John O'Shea and Carlos Tevez put United in charge. Derby improved after the break and Giles Barnes replied from the spot when Paul Green was fouled in the area.Cristiano Ronaldo's penalty seemed to have sealed United's win but Barnes' superb free-kick set up a tense finale.
It is United who have reached Wembley, where they will take on Burnley or Tottenham, but the Championship strugglers still deserve praise for the spirit they showed at Old Trafford when the game looked dead and buried.
It also emphasised how there could have been a very different outcome had Derby made the most of their opportunities in the first leg. (BBC Sport)
