Moves Manchester United Should and Shouldn't Make in the Transfer Market

Manchester United's win over Liverpool at Anfield on Sunday has kept them on course to finish in the Premier League's top four and qualify for next season's Champions League.

But Louis van Gaal is sill expected to spend heavily in the summer to make sure they are challenging for the title next season rather than just fourth place.

Here's a rundown of five potential targets for United this summer, including two who Van Gaal and Ed Woodward would be wise to avoid.

Feel free to use the comments section below to agree, disagree or add your own.

Mats Hummels

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Chris Smalling and Phil Jones are playing well at the moment. But United will still need a new centre-back in the summer. Mats Hummels is one of the best around, even if he does lack a yard of pace. It would also give Van Gaal the ball-playing defender he craves.

It's been a difficult season for Borussia Dortmund, and United might just fancy their chances of turning Hummels' head, especially if they can offer Champions League football.

Kevin Strootman

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Van Gaal knows all about Kevin Strootman after their time together with the Dutch national team. But what Van Gaal doesn't know is whether the Roma midfielder will ever be the same player after his knee injury, which ruled him out of the World Cup.

His latest set-back means he won't return until the start of pre-season training. Roma would likely demand a high price for the 25-year-old. And it would be a risk for United to pay for a player who might never fully recover. Radamel Falcao's situation should serve as a warning.

Gareth Bale

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Booed by his own fans and getting crucified by the press, Gareth Bale isn't having a great time at Real Madrid this season. So if United were hoping to tempt him back to the Premier League, it might be worth asking the question in the summer.

Van Gaal loves players with pace, and Bale has got bucket-loads. Bale was one of Real Madrid's best players last season, but they have got form for off-loading stars and signing someone else. Just look at Mesut Ozil and Angel Di Maria.

Harry Kane

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Harry Kane has scored a lot of goals in his breakthrough season at Tottenham. And United will be in the market for a striker in the summer if Falcao is sent back to Monaco and Robin van Persie's form doesn't drastically improve.

Only 21 years old, Kane is an attractive prospect. But United and Van Gaal should be wary of making him a primary target. It's only his first season as a first-team regular. And there's no guarantee he won't end up being a one-season wonder.

Nathaniel Clyne

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If Van Gaal isn't convinced by Rafael, then he's going to need a new right-back in the summer. Antonio Valencia has filled in for much of the season and has done a good job. But he's not a long-term solution if Van Gaal wants to challenge for the title.

Young and English, Nathaniel Clyne fits the bill for United. The only question is how much it will take to prise him away from Southampton after they drove such a hard bargain over Luke Shaw.