Javi Martinez
Javi Martinez. right, could make an ideal signing for Manchester United this summer. Reuters

There can be no question that Manchester United underperformed this season. Yet it is also true that the squad has lacked investment in recent years and must be strengthened if the club is to again challenge the best in Europe. The identity of David Moyes’s successor has yet to be revealed, although Louis van Gaal is widely expected to be confirmed as the club’s new manager next week. While it is doubtful that Van Gaal, or whoever comes in, will be given the reported £200 million to spend, there will surely be a major overhaul of the squad.

Here are six players the club would be wise to target.

Toni Kroos (Bayern Munich)
Despite having still to agree an extension to a contract that expires in just over a year’s time, it appears that Kroos is set to stay at Bayern Munich for at least another season. However, if United appoint Van Gaal they will surely be minded to reignite their interest. It was under the Dutchman that Kroos made his breakthrough into the Bayern side. A player who can occupy any role in the center of midfield, United would be wise to offer him the love that he doesn’t believe he is getting in Munich.

Mehdi Benatia (Roma)
The exit of Nemanja Vidic, likely departure of Rio Ferdinand and failure of United’s younger center-backs to assert themselves in the first team, means a new center-back is a must this summer. Benatia has been one of the best central defenders in Europe this season and a key part of Roma enjoying the joint-best defensive record in Serie A en route to finishing second. With Champions League action on the way, the Moroccan would be hard to prize away but it would be well with a concerted effort.

Luke Shaw (Southampton)
Whether due to disaffection under Moyes, or his tired mind and legs, Evra has been a liability this season. One of United’s best weapons going forward, the France international’s tracking back has been far less impressive. Shaw is the man United are thought to have identified as the 32-year-old’s replacement and it would be hard to argue about that choice. The 18-year-old is one of the best prospects to emerge in England in some time and is both a capable defender and excellent going forward. He won’t come cheap, but, already one of the Premier League’s best left-backs and only going to get better, he will surely prove value for money.

Marco Reus (Borussia Dortmund)
Manchester United’s collection of wide players, for so long the strength of the side under Sir Alex Ferguson, have been woeful this season. Nani, Ashley Young and Antonio Valencia have contributed very little and it is paramount that the issue is addressed. United’s abundance of No. 10’s makes the issue more complicated, but Van Gaal has always been fond of natural wide players. While Reus doesn’t quite fit that bill, he is more capable starting from a position out wide than either Juan Mata or Shinji Kagawa. Contributing over 20 goals and almost as many assists this season, the Germany international would greatly increase United’s attacking threat. Prizing him away from Dortmund, though, could prove an impossible job this summer.

Javi Martinez (Bayern Munich)
While Kroos may prove unattainable ion the upcoming transfer window, United could have more luck with fellow Bayern midfielder Javi Martinez. The former Athletic Bilbao man has the physicality that has long been missing from United’s midfield, while also being more than capable on the ball. It appears he doesn’t exactly fit into Pep Guardiola’s plans, at least as a midfielder, having often being used as a center-back. Recent reports suggest that Arsenal have made an inquiry for his services. If the Spain international is available, then it would be negligent of United not to make a move.

Jordy Clasie (Feyenoord)
If Van Gaal is looking for a younger midfield option that he can groom, then he could well turn to a player he has brought through in the Dutch setup. Clasie, 22, is set to go to the World Cup with Van Gaal this summer and has been dubbed the new Xavi. That kind of comparison probably does Clasie little favors and he is certainly not yet the finished article. But in addition to his accomplished passing, he is a proficient tackler and has the dynamism to make him a strong presence without the ball.