3. Kolo Toure (£167,000):
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Today, Kolo Toure isn't fondly remembered for his stellar defensive performances. He, unfortunately, became something of a joke after a disappointing few seasons at Liverpool. Before all of that though, Toure was a hungry youngster so eager to impress Arsene Wenger, that he tackled Henry, Bergkamp and the manager himself whilst on trial at Highbury.
Pound for pound, Toure could be regarded as one of the best signings ever. He was an important part of the Invincibles side, making 37 league appearances. Halfway through the first decade of the 21st century, Toure had become one of the finest centre-backs in the English game.
The end to his time at Arsenal was as the result of a bust-up with William Gallas, but his move to Manchester City netted Wenger's side a solid £16.83 million. It still befuddles the mind how Wenger managed to pluck a gem like Toure for only £167,000.