5 worst transfers of the Bundesliga season

Hope entering the season often turned to frustration after transfer gambles failed to offer adequate returns on investment during the marathon Bundesliga campaign.

Here's a collection of the five biggest transfer busts in the Bundesliga this season:

Aleksandar Dragovic - Bayer Leverkusen (£15.30m)

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Bayer Leverkusen likely would've done things differently last summer after splashing out over €15 million to acquire Aleksandar Dragovic from Dynamo Kyiv.

Instead of providing a boost to Leverkusen's backline, the Austrian centre-back struggled to justify his price tag within a squad that suffered one of the biggest drops in the table compared to its third-place finish during the 2015-16 campaign.

Dragovic's inadequate play at the back was one of the reasons Leverkusen allowed 15 more goals than last season and finished in 12th place with 55 goals conceded.

Benjamin Stambouli - FC Schalke (£6.80m)

(Photo courtesy: Action Images)

Benjamin Stambouli can't seem to catch a break.

Unlike his frustrating season with Paris Saint-Germain last year, Stambouli came nowhere near close to lifting a league title in his first season in Germany as part of a bitterly disappointing FC Schalke outfit.

After claiming that the Bundesliga "is the best league for me," the 26-year-old Frenchman did little to stem the tide as Schalke finished 11 points off last season's pace.

Holger Badstuber - FC Schalke

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FC Schalke's answer to its woes coming out of the winter break did little to resolve the club's first-half frustrations as Holger Badstuber proved ineffectual during his half-season loan from Bayern Munich.

The oft-injured centre-back managed to keep a clean bill of health, but seemingly did more harm than good as Schalke only managed to win two matches with Badstuber on the pitch.

Despite his struggles, Badstuber will likely attract some interest on the open market, especially among teams familiar with the potential he showed at Bayern before his career was continuously interrupted by major injuries.

Yunus Malli - Wolfsburg

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After allegedly piquing Tottenham's interest last summer, it seems likely that the Premier League side won't come knocking on Wolfsburg's door to inquire about Yunus Malli in the coming months following his horrid second half of the season.

The Turkish international was a hot commodity following a 2015-16 term in which he banged in 11 goals and set up four others with Mainz ahead of his summer switch to Wolfsburg.

But, following an impressive start to life at Wolfsburg, Malli pulled off a disappearing act after the winter break. He only managed one goal in the final months as Die Wolfe find themselves set to compete in a relegation play-off.

Renato Sanches - Bayern Munich

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A combination of a massive transfer fee and mediocre performances make Renato Sanches the Bundesliga's biggest transfer flop.

That's not to say the gifted midfielder doesn't have a future with Bayern Munich, but Sanches must make his mark next season to justify the £29.75 transfer fee that Benfica received last summer following the 19-year-old's breakout performance during Portugal's triumph at Euro 2016.

Of his 17 league appearances, only six came as a starter as manager Carlo Ancelotti often introduced Sanches into matches with little at stake in order to give his regulars a breather.