Even the legendary Sir Alex Ferguson wasn't immune to transfer mistakes at Manchester United.
The captures of Eric Djemba-Djemba, Dong Fangzhuo, Kleberson and Juan Sebastian Veron stick out like soar thumbs in an otherwise immaculate 27-year tenure at Old Trafford.
However, the transfer windows of 2008-09 saw Ferguson carry out some decent business ahead of another Premier League title win. The brothers Fabio and Rafael joined the club as well as Dimitar Bebatov in a last minute coup from Tottenham.
There was one more signing that season, though, and it didn't work out quite as well.
The man in question is Zoran Tosic who left Partizan Belgrade for the mother of all transfers and under the mother of all pressures. Not only had Tosic signed for arguably the world's biggest club but he was mooted as the long-term successor to Ryan Giggs.
Ryan Giggs' potential successor
When you consider Giggs accumulated 13 Premier League titles, four FA Cups, two Champions League victories and 963 appearances in the famous red jersey, they're some boots to fill.
As per the Guardian, the official Man Utd website mused at the time: "It could be Tosic who is charged with filling the Welshman's boots when [Ryan] Giggs eventually retires."
The British media certainly had no objections to that claim with both the Guardian and the Telegraph suggesting Tosic could be the man to inherit the mantle. After all, the Welshman would reveal in the New Year of 2009 that he was indeed preparing for retirement.
So, that's well and good, but what actually happened?
Ferguson was very keen to push through the deal, even personally attending his work permit hearing to ensure it was given the green light but only ever granted Tosic five substitute appearances with the Red Devils.
A failure to improve after a stale opening season and a poor physique for the Premier League saw him loaned out to Cologne where a flurry of goals saw him selected for Serbia's World Cup squad in 2010.
His performances in South Africa didn't turn the tide, however, with United's eyes lighting up at an £8 million offer that arrived from CSKA Moscow.
Tosic would take residence in the Russian capital for the next seven years, earning 241 appearances and finding the net on 47 occasions. Silverware also came in the form of three league titles and two Russian Cup wins.
Back to square one
However, Tosic eventually left in 2017 and it brought his career full circle with a return to Partizan.
There's obviously a certain romanticism to returning to the club that made you but proceedings might seem a little premature for Tosic at age 30. Just under a decade from his dream move, he is very literally at square one.
Nevertheless, it goes without saying that the midfielder made a decent career for himself even if his choice of clubs took him off the beaten track.
No Giggsy, mind.
Do you think anyone will every match Ryan Giggs at Man Utd? Have your say in the comments section below.
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