As Manchester United’s first season under manager Louis van Gaal draws to a close, the club finally know they will be playing in the Champions League again next season — but may have to win a two-legged qualifier in August.

As Van Gaal looks forward, however, there are burning issues to address regarding key players.

Here, Sportsmail look at all of these issues in detail.

IS DAVID DE GEA DEFINITELY LEAVING FOR MADRID?

United are still talking to David de Gea and his advisers and are hoping that a record deal for a goalkeeper — in excess of £200,000 a week — will persuade him to stay.

As recently as last week, United executives were voicing hopes that a display of support from the club’s fans during Sunday’s game against Arsenal may help to turn De Gea’s attentions back towards Old Trafford.

David de Gea has been heavily linked with a move to Real Madrid this summer

The United No 1 has come a long way since his Athletic Madrid playing days (above)

Inside the dressing room, however, hope is fading fast with players saying privately after the 1-1 draw with Arsenal that they feel the Spaniard is definitely on his way to Real Madrid.

Van Gaal’s public stance on the matter has certainly changed.

For weeks, he refused to discuss the issue but recent pronouncements suggest that United have a list of replacements lined up and an admission that De Gea is being pulled towards Madrid by his girlfriend indicate that United know they are in the closing stages of a battle they may well lose.

Sportsmail takes a look at the goalkeepers who could replace De Gea should he choose to leave Old Trafford

WHAT IS THE CONTINGENCY PLAN?

De Gea has shown this season how vital it is to have a world-class goalkeeper and Van Gaal has already discounted beginning next season with his current understudy Victor Valdes.

For all his experience and quality, Valdes will begin the next campaign as No 2.

In terms of a replacement for De Gea — if that is what it comes to — United are more than aware of the qualities of Tottenham’s Hugo Lloris and Petr Cech of Chelsea but know they will face enormous battles to get either from their current clubs.

Victor Valdes (righty) will not be Manchester United's No 1 next season despite De Gea's likely departure

The former Barcelona keeper made his debut - five months after joining the club - against Arsenal on Sunday

United scouted both keepers in the years of Sir Alex Ferguson but Tottenham, for example, have already been telling people that they will not sell Lloris to United.

The Old Trafford board are well aware of how Spurs chairman Daniel Levy digs in his heels whenever they come knocking for players. With all this in mind, one other goalkeeper who is already under consideration is Dutch No 1 Jasper Cillessen of Ajax.

WILL UNITED TRY TO LAND BALE IN A DE GEA DEAL?

At the moment, United do not want to do this. They simply do not want to encourage Real into thinking that they are actively looking to sell their goalkeeper.

Given the choice, Van Gaal would rather begin next season without the Wales winger if it meant hanging on to De Gea.

However, that stance may change somewhat if it becomes clear that De Gea is going to leave anyway.

Gareth Bale looks horrified as Gianluigi Buffon urges his defence to think after the Welshman blazes over

The former Tottenham star turns the wrong way as Real Madrid fans hurl abuse at their forward

The former Tottenham forward is reportedly unhappy with life in Spain and could join United this summer

United have the money to do the Gareth Bale deal and will break the world transfer record if they feel they must. United and their chief executive Ed Woodward are currently unsure about whether Bale will be made available this summer. If he is, they will be at the front of the queue.

United first became aware of Bale when he was a teenage left back at Southampton and were very much involved in discussions before he moved to Spain from Tottenham two summers ago.

WHAT ABOUT FALCAO AND ROBIN VAN PERSIE?

Falcao’s wave to the crowd on Sunday seemed to signify the end of the Colombian’s time at Old Trafford.

There have been suggestions from Falcao’s entourage that an extension of his loan through to January may have been a possibility worth discussing.

United, however, have not confirmed this. They are aware that they will need strength in depth next season with the return of European competition and there could have been some mileage in the possibility of Falcao remaining as a back-up on reduced terms.

Falcao waves to fans after being substituted against Arsenal, fuelling speculation he will be leaving United

Robin van Persie, who replaced the Colombian forward on Sunday, is expected to remain at Old Trafford

Nevertheless, the player himself understandably wants to play at a club where he will be a frontline striker and is currently listening to other offers from around Europe, including one or two from the Barclays Premier League.

With regard to Van Persie, it is highly likely he will stay and may even talk to the club about an extension to a contract that has one more year left to run.

The Dutch international would ideally like to remain at Old Trafford but United will need to do something to protect his sell-on value if that is to happen.

The difference between Van Persie and Falcao is that the former knows how to score goals in this division and Van Gaal does feel that he can contribute fully next season if he can stay fit.

WHAT DOES DEPAY SIGNING MEAN FOR DI MARIA?

In short, whether or not Angel di Maria has a future at Old Trafford depends entirely on the Argentine forward himself. The signing of Memphis Depay from PSV — who had a medical at United on Monday — will not influence that at all.

United will play more games next season and Van Gaal knows he needs greater alternatives in different positions if his squad is to thrive.

Memphis Depay celebrates after scoring against Heracles in his last home appearance for PSV Eindhoven

Depay scarves were sold outside Old Trafford on Sunday ahead of the Premier League match with Arsenal

As Van Gaal himself hinted recently, Di Maria has been found wanting mentally this season and only the player knows whether he has the capacity to reverse that.

United have been sympathetic in helping Di Maria and his wife and daughter get over the attempted burglary they suffered in the winter, with the club allocating support staff and security to the family.

However, on the field Di Maria has been left in no doubt about the ways he must improve. United do not want to sell Di Maria and they do not wish to loan him out. If he does leave this summer, it will be because he asks to.

P.S. If United finish the Barclays Premier League season in fourth, they will have to qualify for next season’s Champions League group stage.

Luckily for them, a seeding system based on the UEFA Club Coefficient should spare them a difficult meeting with teams who enter at the same stage: Valencia or Sevilla (fourth in Spain), Bayer Leverkusen (fourth in Germany), Roma, Lazio or Napoli (third in Italy), Sporting Lisbon (third in Portugal).