Manchester - Manchester United manager Alex Ferguson has praised the mental resilience of goalkeeper David de Gea as the Spaniard prepares to face Blackburn Rovers again.When Blackburn upset the odds to beat United at Old Trafford on New Year's Eve, De Gea was blamed for Grant Hanley's winner and was subsequently left out for four games.He might have remained on the sidelines at the Premier League leaders and reigning champions if Anders Lindegaard had not suffered an ankle injury in training but is now making a case to be named first-choice 'keeper.The Spain under-21 international, who made an excellent injury-time save to keep out a free-kick from Chelsea's Juan Mata upon his return, is set to be between the posts again when United play Rovers at Ewood Park on Monday.A win for United would send them five points clear at the top of the table.Ferguson compared De Gea's fortitude to that of Rovers manager Steve Kean who, having suffered a torrent of abuse and calls for his resignation from his own supporters earlier in the season, has now led Blackburn to a position where they have a fighting chance of avoiding relegation."It's similar to what we were saying about Steve Kean," said Ferguson. "He got a grip of it and stood up as a man."The area where he (De Gea) has been been criticised was the aerial ability in the box. He should have dealt with the last corner against Blackburn better. He knew that."He has addressed that section. He didn't let it get to him and now the boy is playing with confidence. And confidence is a great factor in football."Although the 21-year-old has some way to go before he can be considered a United goalkeeping great alongside the likes of Peter Schmeichel and Edwin van der Sar, Ferguson believes De Gea is on the right track."It took him time to adapt to the different ways of the English game and he is showing that now," said the veteran United manager."The other night (in the 1-0 win against Fulham), he made two or three really terrific punches and blocks in the first and second half when they started to propel the ball into the box."He has shown fantastic improvement. We expected his ability to show and we are seeing that now."Following Manchester City's failure to beat Sunderland on Saturday, United now have a chance to tighten their grip on the title.Their next three fixtures - against Blackburn, QPR and Wigan Athletic - see them up against teams battling to avoid the drop but Rovers have won two of their last three games."We know how quickly football can turn on you and bite you," said Ferguson."You can look at all the fixtures and say all those teams are fighting for their lives. And they are the kind of games you know will be tight."