But Alexander Hleb will struggle to be fit to face his former team at Wembley after being carried off midway through the first half, the victim of a clattering foul by James O'Connor.
Three and easy: David Murphy scores Birmingham's third goal
McLeish admitted that Hleb is aserious doubt and said: 'Hopefully he'll be OK for Wembley but he got afair rattle and the guy was very late with the tackle.'
Cup cheer: Obafemi Martins (second right) celebrates opening his account for Birmingham
Wednesday manager Gary Megsonexonerated his player of blame, saying: 'It was a mistimed challenge byJames but he didn't do it deliberately. We hope that Hleb's OK.'
MATCH FACTSBirmingham (4-4-2): Doyle; Carr, Parnaby, Johnson (Mutch 62min), Murphy; Beausejour, Bowyer, Hleb (Bentley 26), Fahey; Martins, Jerome (Phillips 46). Subs (not used): Foster, Larsson, Gardner, Zigic. Booked: Johnson.Sheff Wed (4-4-2): Weaver; Spurr, M Morrison (Beevers 46), R Johnson, Reynolds; Teale, O'Connor (Palmer 46), Osbourne, Jones; Mellor, C Morrison. Subs (not used): Jameson, Heffernan, Potter, Sedgwick. Booked: O'Connor, Spurr, Beevers, Johnson.Referee: A Taylor (Cheshire).
Cameron Jerome also limped out withan ankle injury but is expected to recover in time, while RogerJohnson, having been booked, was taken off as a precaution.
Wednesday made the worst possiblestart, conceding after only six minutes when Jean Beasejour was leftunmarked at the back post to steer in Lee Bowyer's cross.
Obafemi Martins punished them further by bursting past a feeble challenge from Michael Morrison before firing past Nicky Weaver.
David Murphy smashed home the thirdfrom close range after what appeared to be a foul on Weaver by Bowyer,but Megson, without a win in four matches in charge, didn't have theheart to protest.
'It might have been a foul,' he said, 'but we were just not strong enough.'
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