Stepney told the Manchester Evening News: "United will have worked on things this week.
"De Gea has turned in some good performances for United and like most of todays' keepers, he is what I term a shot-stopper.
"His distribution is good.
"Lindegaard had a run in the United team last year and then got injured before his recent spell.
"But, at times, no authority at the back was shown against Reading.
"Having said that, maybe it's better for United not to have played all that well but still picked up three points and then have things sorted out ahead of the clash with City."