Ferguson anticipates either "a very open game" or "an intense battle", depending on whether City come to make a game of it. Ball, who described it as the biggest game of his managerial career, said: "We're going into the lion's den and hopefully we'll tweak its tail."
He will be without his captain, the suspended Garry Flitcroft, whereas United welcome back their skipper, Steve Bruce. Neither development enhances City's prospects of ending a 12-game run without a win over their neighbours dating back to 1989.
Maine Road has waited even longer for silverware - since 1976 in fact - which is a feeling Aston Villa fans recognise when the Cup comes around. Villa have now gone 39 years without winning the trophy, a strange anomaly given their tally of seven final victories, not to mention championship and European Cup successes in the interim.
A trip to Ipswich, a middling First Division outfit, offers a better then even chance of reaching the quarter-finals, especially with Dwight Yorke on a hot scoring streak. Even allowing for the Suffolk side's win at Blackburn, over-confidence and a pitch that looks as if it recently staged the Horse of the Year Show may prove Villa's worst enemies.
George Burley, the Ipswich manager, may have been seeking to foster complacency in his visitors when he said: "There's not a better team in the Premiership than Villa at the moment, and we'll have to be at our best to make it a decent game."
The tie at Huddersfield's new McAlpine Stadium is a bit of a collectors' item: an all-ticket match involving Wimbledon. Brian Horton's men would doubtless have preferred to be facing Middlesbrough, not only because the Teessiders are eminently beatable right now but because they would have attracted a full house.
The First Division's third-placed club have not reached the last 16 since 1972, when Frank Worthington scored in the defeat of West Ham. On the same day Wimbledon won at Merthyr in the Southern League, and yet a Huddersfield victory would be classed as a giant-killing.
Having narrowly avoided being shunted into the Cup sidings at Crewe, Southampton's tour of railway towns continues at Steve McMahon's Swindon, two places above Crewe at the Second Division summit. The Swindon midfield player Paul Allen, a Wembley winner with Spurs in '91, and still the century's youngest FA Cup finalist - he was 17 years, 256 days old when he helped West Ham beat Arsenal in 1980 - has a point to prove to Lawrie McMenemy. According to Allen, his time at Southampton was up as soon as McMenemy returned as football director.
"He obviously didn't rate me but what upset me was that it was never discussed with either him or Alan Ball," Allen said. "Dave Merrington [Ball's successor] was very fair to me, but I've been glad to come to a club where you respect the manager and he gives you a fair chance."
Shrewsbury should give a good account of themselves in tomorrow's delayed fourth-round tie with Liverpool. But thoughts of Bob Paisley will make Liverpool equally determined to ensure Gay Meadow does not become a field of dreams.Reuse content