The players Louis van Gaal needs to sign to make Manchester United title contenders next season

Part one is done, barring a shambolic finish to the season, but there is plenty to do if they are to take the title from Chelsea in 2015-16. United are not as good as they looked when they thrashed Manchester City; nor as they as bad as they looked when they walked into Everton’s trap on Sunday.

Van Gaal has withstood some heavy criticism – or, more likely, ignored it – this season. Those dynamic performances against Spurs, Liverpool and City have probably bought him immunity from any significant criticism until the start of next season, which means he should be able to go about a vital summer’s work in relative peace. In an ideal world, that will involve a centre-back, a right-back, a central midfielder, a winger and a striker. They need to significantly improve both the first XI and the squad, given the increased demands of Europe.

The defence has done much better than expected this season – since that desperate fiasco at Leicester in September they have only conceded more than one goal in four league games – though part of that is down to David de Gea and the protection offered by United’s tiki-takanaccio possession game. Marcos Rojo, Phil Jones and Chris Smalling have all had decent seasons but none are top class, not yet, and all are exasperatingly injury prone. United don’t just need a high-class centre-half; they need one who has little history of injury problems. Aymeric Laporte is only 20, though he seems the likeliest candidate at the moment.

Antonio Valencia has done well enough in his first full season as a right-back but makes too many individual mistakes to be a credible long-term option. Rafael’s impetuous nature clearly is not for Van Gaal, so it would not be a surprise to see someone like Nathaniel Clyne – who almost joined United in 2012 – move to Old Trafford this summer.

The apparently inevitable signing of Roma’s Kevin Strootman has been complicated by his injury problems, though United will surely sign someone in that area. Borussia Dortmund’s Ilkay Gundogan is the best available option. Ander Herrera, though weirdly overrated, has had a good first season, and Michael Carrick – the new darling of English football, at the age of 33 – should be fine for at least another season. Marouane Fellaini remains an extremely useful option, though whether such a player would be a regular in a putative title-winning XI is open to debate. Now that Van Gaal seems to have settled into a classical 4-3-3 formation, he might prefer another footballer in that position.

On paper, he already has the perfect man. Angel Di Maria generally played to the left of centre during his sparkling start to life at United, and at his best would give United much needed penetration with his dribbling. But there are plenty of signs that Di Maria is not going to come back from his problems this season, not at Old Trafford. So far his United career has followed an identical pattern to that of Juan Sebastian Veron; Sir Alex Ferguson – after telling the press they “youse are all f*****g idiots” and that Veron was “a great player” - gave Veron a second season, in which he did little of note before being sold at a significant loss that summer.

Then again, Robert Pires had a pretty poor first season at Arsenal, and followed that up with the FWA Footballer of the Year award in his second. Nobody really knows anything, but the judgement Van Gaal takes on Di Maria could be his most important of the summer. Depending on what happens with the Argentina international – whether he goes, or where he plays if he stays – United may want another winger, with Van Gaal apparently very keen on Memphis Depay.

There are other hard decisions to take, not least over Robin van Persie. There is compelling evidence – almost two years’ worth – that Van Persie was a one-season wonder at United, and has never really got over the retirement of Ferguson. The other advantage of selling Van Persie is that it will reduce the temptation to play Wayne Rooney in midfield.

As a No. 9, Rooney is a shadow of the player he was when he cleaned up the individual awards in 2009-10. He will be 30 in October and has a serious amount of mileage on the clock. But his finishing, once erratic, is now extremely accomplished and easily his strongest suit, while he offers significantly more desire and movement than Van Persie. The decision not to sign Falcao permanently should be sadly straightforward. That means United need another striker to support Rooney and James Wilson. It has to be somebody who can play up front of his own, if United are to continue with 4-3-3. Danny Ings looks a decent value option, perhaps with Wilson going out on loan for a year.

With Rooney, Van Persie, Falcao, Juan Mata and others, United’s attack looks great on paper, albeit in the year 2012. In 2015 they have a sterile domination problem, with all that possession often not amounting to much. United have the highest average possession in the Premier League this season (60.7 per cent), but their average of 13.4 shots per game puts them eighth. That is an obvious dichotomy. The answer seems obvious: a higher tempo and a more decisive approach, which worked against City, Spurs and Liverpool. Yet if it was really that simple, you suspect a manager as good as Van Gaal would have spotted it.

Van Gaal’s other big task is to try to persuade De Gea to stay at United. The likeliest scenario is that he will go, to be replaced by Victor Valdes. If that is the case, United should help themselves to the pick of Real’s cast-offs. Every year Real clear out some extremely good players, like fashionistas throwing away an outfit they have only worn once because they are bored of it; and, while they usually get good money for such players, it is different if they are part of a swap deal for a player Real desperately want.

In 2009, when Cristiano Ronaldo joined Real, Ferguson missed a trick by not making Arjen Robben and/or Wesley Sneijder part of the deal. Instead they joined Bayern and Inter respectively that summer, and both went on to win the Treble. There are a few possible Real rejects who might interest United, including Sami Khedira and Gareth Bale. There has been a bit of a backlash against Bale lately. Let’s be clear about this: he would run riot in the Premier League.

Whether he’s Van Gaal’s type of player is another matter. Beyond the fact that he likes young players, who are more malleable, and Dutch players, who are familiar with his philosophy from his time with the national team, it’s very hard to predict who Van Gaal might want to sign because he has a unique way of judging players. He sees football through different eyes. This is a man who bombed out Lucio as soon as he joined Bayern Munich, for example, and was regularly losing his rag with Rivaldo’s tactical indiscipline at a time when most thought he was the best player in the world. There have been successes too; he saw things in Jari Litmanen, Thomas Mueller and David Alaba that many others did not.

It’s clear that certain players are incompatible with his philosophy, even if – let’s be honest here – none of us really have a clue what his philosophy is beyond the obvious virtue of keeping possession. There really is no point trying to predict who Van Gaal might sign, so that’s exactly what we’re going to do. With around £100m net spend, assuming De Gea goes, this might be United’s first XI next season: Valdes; Clyne, Laporte, Rojo, Shaw; Carrick; Di Maria, Herrera; Depay, Rooney, Bale. With that, the second step of Van Gaal’s three-year plan might just be possible.