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The consequences of Manchester United’s front office spending sprees on questionable players over the past five years is finally beginning to hurt the squad.

Fans have been calling for the Glazer family to step down as owners for what supporters believe is a lack of spending and bleeding the club dry. However, United have been active on the transfer market over the last few summers and have been more than generous with their money.

Since the summer of 2009/10, the same year Cristiano Ronaldo was sold to Real Madrid, United has spent a total of £290.7 million, per Transfermarkt.com. Some of those signings—like Robin van Persie—paid dividends, but even Van Persie's starting to pick up niggling injuries and miss games.

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Players like Juan Mata and Shinji Kagawa are talented, but they don't fit into the Man United system. They should not have been acquired, especially given the lack of central defenders and deep-lying midfielders in the squad.

Chris Smalling, Phil Jones, Wilfried Zaha and Bebe were thought to be future stars for the club but haven't lived up to those expectations as of yet. They were brought in for a combined £37.7 million, according to Transfermarkt.com.

Marouane Fellaini was a panic buy, Ashley Young turned out to be a flop and Antonio Valencia has demonstrated that he's a winger with a lot of strength but struggles to play on his weaker foot, and his passing is erratic.

Not every acquisition over the last five years was a bad decision. David De Gea was a smart deal, even 19-year-old Luke Shaw could be a good buy, but it's still too early to evaluate. Shaw was brought in as a future prospect for a position that was vacated when Patrice Evra went to Juventus.

The board has also been irresponsible with some contract negotiations. Nani was given a sizeable raise from approximately £90,000 to £130,000 per week, per NBC's ProSoccerTalk, which is a disproportionate salary for such an average player.

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Wayne Rooney earns about £300,000 per week thanks to his new deal, according to Forbes. That makes the Englishman one of the 10 highest-paid players in the sport, which isn't indicative of his actual abilities. There are many others who make far too much, including the aforementioned Ashley Young.

Money has always been readily available for United. The fact that Sir Alex Ferguson was given too much trust ended up hurting the team. Ferguson's man-management skills were able to mask the ongoing issues with the defence and midfield. Van Persie's 26 league goals in the title-winning 2012/13 Premier League season were also vital.

United's failures in the transfer market have nothing to do with unavailable funds. It comes down to horrible planning and lazy scouting. Filipe Luis, Cesc Fabregas, Luiz Gustavo and Luka Modric could have been acquired for a cheaper price than Shaw and Ander Herrera.

There are plenty of bargains and long-term investments in the market. Thiago Silva joined PSG for around €42 million, per Goal.com, but that's still cheaper than the club's record signing of Mata.

Rio Ferdinand, Nemanja Vidic and Patrice Evra were all leaving, and United had plenty of time to prepare for those departures. They failed to do that and now they're scrambling to fill the holes in the squad.

This is the reason that the Red Devils have signed Sporting Lisbon defender Marcos Rojo, with Nani joining the Portuguese side on loan, per Chris Wheeler of the Daily Mail.

Rojo is an average squad player, but for £16 million and Nani on loan, it's a high price. This is another example of ineptitude from the board in the transfer window.

This debacle has nothing to do with the Glazers being cheap. The money has been available. It's been spent poorly, and now it's showing with United's mediocre performances in the Premier League.