The Spain Under 21 star has endured a shaky start to his United career. De Gea made high-profile mistakes in his first two matches, and even in the eight-goal destruction of Arsenal last month, he was criticised for letting a Theo Walcott shot fly through his legs.
However, he came through what was expected to be a searching examination at Bolton a fortnight ago without a problem, amid pre-match rumours he was about to be left out.
Tough start: David De Gea (left) has struggled so far since arriving in England
Ferguson expects in-form Stoke to provide more of a threat, particularly with Peter Crouch available to Tony Pulis. And the United boss has taken a routine from Edwin van der Sar's time at the club to ensure De Gea is fully prepared.
'It's an eye-opener for any goalkeeper,' said Ferguson. 'I remember discussing with Edwin what his position would be in terms of the long throw-ins and where he was most comfortable dealing with the situation.
'We got it right then and we are doing the same with David. All the work this week has been on his position and where he should be.'
Although visits to Stoke tend to be looked upon with trepidation by most of the Premier League's top clubs - Chelsea and Liverpool have both failed to win there this season already - United have a faultless record against Tony Pulis' men in six meetings since they were promoted.
Eye on the ball: The Spanish goalkeeper is ready for Stoke's aerial threat
Another victory would be a sixth straight win for United, who have established a two-point lead at the Premier League summit, which would be their best start since winning 10 in a row under Ron Atkinson in 1985.
Not that Ferguson is allowing himself to get too concerned with statistics. All he cares about is where his team finishes.
'There is no point analysing our start in terms of previous years,' said the United boss. 'I am just enjoying the moment and hope it lasts longer than normal.
'You know somewhere along the line we will lose a game or drop a point. That is a fact. That is the league we are in. Does it matter if you win the league? No it doesn't. You deal with the situations as they come along. If we have a defeat, the next week you try to win.'
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