#3 Roque Santa Cruz
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He was brought to Blackburn Rovers having had stunning form for Paraguay and giants Bayern Munich. €5 million seemed like a sensational bargain for a striker who served as understudy at one of Europe's biggest clubs.
He hit the ground running, scoring 19 times in 37 games in 2007-08 finishing 4th in the season's top scorer list. He was behind only Cristiano Ronaldo, Fernando Torres and Emmanuel Adebayor as Blackburn overachieved with an eighth place finish.
Almost as soon as Blackburn believed they had a goal machine on their hands, the goals dried up as he scored just nine times in the next 27 games. Amazingly, Manchester City came with a £17.5m for his services on a four-year deal, leading Blackburn to cash out on their star man. Sadly he scored just four times for Manchester City and was largely persona non grata.
#2 Robinho
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Robinho was touted as a generational talent and the next Ronaldo Nazario for his sharp pace and clinical ability to beat a marker. He was signed by Real Madrid as a galactico and given the number 10 shirt for good measure. He delivered by being the third top scorer in his three seasons at Madrid, even finishing top 10 in the Ballon D'or rankings.
As fickle as Real Madrid are however with management and change, Robinho was sold to Manchester City for a then eye watering 32 million pound move. This was the Cityzens' first ever marquee signing under the Abu Dhabi sports group.
In his first full season he was fourth top scorer with 14 goals in the Premier League in 2008-09, topping the club charts. Promise, however, turned to inconsistent disappointment and injury troubles which saw him miss up to three months of next season with just a single goal. Manchester City promptly sent him packing out on loan to Santos after which he never played for the club.
#1 Michu
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Perhaps the most memorable and influential "one-season wonder" in all of modern football. He was signed for just £2 million from Rayo Vallecano. Few expected the attacking midfielder/centre forward to explode onto the scene with a silky smooth technique and a penchant for the spectacular.
His 2012-13 season saw him score 18 goals in just 35 games, finishing in the top five on the scoring charts.
What made him stand out was the class and comfort he had on the ball, despite being a tall, physically imposing player. He possessed a lethal left-foot shot that found the top left corner of the net with surprising regularity.
He even had a trophy to his name as Swansea City ran out as League Cup winners that season in a massive upset. Sadly, a career plagued by injuries meant Michu's star shone very briefly before he retired aged just 31 years