Manchester United made it back-to-back wins in the Premier League for the first time this season to catapult themselves into the top four for the first time in 14 months with a hard fought 2-1 victory over Everton at Old Trafford on Sunday. Following the media’s overreaction to an admittedly under par first five games, United and their plethora of impressive summer acquisitions have begun to show the potential this new look side has in abundance.

The Toffees may have started the season poorly themselves, sitting in a lowly 17th position in the Premier League and coming off the back of a lengthy trip to Russia to face Kuban Krasnodar in the Europa League on Thursday night, but the match was most definitely Louis Van Gaal’s biggest test as United boss to date. The Dutchman passed it with flying colours, making two enforced changes to the line-up against West Ham last week, with Antonio Valencia and Juan Mata replacing the injured Ander Herrera and the suspended Wayne Rooney respectively.

The Spaniards inclusion in particular paid dividends as he set up record signing Angel Di Maria for a superb curling opener. After Steven Naismith’s header drew Everton level, the former Real Madrid midfielder then turned provider as his miss-hit shot found Radamel Falcao in the area, who poked home his first for United to move the Red Devils into the Champions League places.

Here are five things we learnt from Sunday’s victory.

1. David De Gea has world class potential

Last season’s player of the year was the star of the show as he made several unbelievable saves to preserve United’s lead, including brilliantly denying Leighton Baines from the penalty spot just before the break. Incidentally, he is now the only goalkeeper in to stop a Baines penalty in the Premier League. De Gea has received some unjust criticism from some quarters at the beginning of the season for his lack of saves in the first six games but the Spaniard showed that he has incredible, world class potential here.

Not many keepers in the world can match the 23-year-old’s fantastic reaction time when a shot flies in his direction. His reflex saves from Leon Osman and Bryan Oviedo shots late on proved that United have a reliable keeper who is capable of winning them points in crucial games such as this one. The two points which he saved for the Red Devils could be so valuable come the end of the season.

2. Falcao is a predator and a match-winner

Falcao’s celebration following his match-winning strike said it all. He is so happy to be at United and is determined to make his stint at the club a success. You could see the sheer relief as he poked home Di Maria’s off target shot to restore United’s lead. Now the Colombian has got that all important first goal for the club, you get the feeling that the goals will now start flowing and Falcao will play with more freedom, letting his instinct take over.

Van Gaal said it himself; Falcao was trying too hard to get that first goal. He is a predator in front of goal whose instinct for a goal cannot be matched. Since moving to Europe, he averages more than a goal a game. He is one of, if not the most rounded striker on the planet and United will surely reap the rewards for securing his signature in the coming months.

3. United still need key defenders to return

Although it was a pleasing victory for United, the defensive frailties and inability to keep the opposition at bay for 90 minutes reared their ugly head once more. Paddy McNair has had a stellar first couple of games for the club but it is vital that key and more experienced defenders such as Phil Jones, Jonny Evans and Chris Smalling return from injury during the international break.

United were unable to keep a clean sheet once again as Naismith instinctively nodded in Everton’s equaliser. There was far too much space for the Scot to sneak into the six yard box and head past De Gea, further proving that Unted’s defence is in desperate need of a leader. A pairing of Jones and the passionate Marcos Rojo looks like it could be the way forward once the Englishman’s hamstring recovers. Either way, Van Gaal needs to settle on a regular pairing when his injuries return.

4. Three wins in a row at home, the return of fortress Old Trafford?

The victory means it is now three wins in a row at Old Trafford for United. Just like old times. This never happened under Van Gaal’s predecessor David Moyes and it is a statistic which will please the 63-year-old as he made it one of his primary aims when he took the job to restore the fear factor that has gone missing at the Theatre of Dreams.

Following a patched up United side opened the campaign with a defeat to Swansea, the new look United have beaten QPR, West Ham and now Everton. Next up at Old Trafford is league leaders Chelsea and if United could pick up a result against Jose Mourinho’s side, that would send out a massive statement. Fortress Old Trafford would be well and truly back.

5. United impressive without captain Rooney

Rooney’s moment of madness against West Ham last week may have been a blessing in disguise for Van Gaal. The Dutchman was able to see his side in action without Rooney without needing an excuse to drop him. He saw his re-built United team play impressively without their new captain with Mata taking Rooney’s place behind Robin Van Persie and Falcao. I have seen the term ‘un-droppable’ being used to describe Rooney at the start of the season but there is not a chance that this should be the case.

The captain is an important player for United but the sheer volume of attacking talent at the club means that his place in the team should by no means be a guarantee. Mata is arguably a better no.10 than Rooney whilst Van Persie and Falcao are more prolific strikers. It is likely he will return to the side following his suspension but the performance in the Everton win means Rooney must up his game when he returns as it showed there are alternative options for Van Gaal to mull over.